Merge branch 'master' into stream_corked_pr

86 files changed, 1279 insertions, 778 deletions

diff --git a/src/core/ext/client_channel/channel_connectivity.c b/src/core/ext/client_channel/channel_connectivity.c
index dd70bc2c6c..f6cb3b9115 100644
--- a/src/core/ext/client_channel/channel_connectivity.c
+++ b/src/core/ext/client_channel/channel_connectivity.c
@@ -139,8 +139,8 @@ static void partly_done(grpc_exec_ctx *exec_ctx, state_watcher *w,
     error = GRPC_ERROR_NONE;
   } else {
     if (error == GRPC_ERROR_NONE) {
-      error =
-          GRPC_ERROR_CREATE("Timed out waiting for connection state change");
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+          "Timed out waiting for connection state change");
     } else if (error == GRPC_ERROR_CANCELLED) {
       error = GRPC_ERROR_NONE;
     }
diff --git a/src/core/ext/client_channel/client_channel.c b/src/core/ext/client_channel/client_channel.c
index 960d00e815..435a3ab0fe 100644
--- a/src/core/ext/client_channel/client_channel.c
+++ b/src/core/ext/client_channel/client_channel.c
@@ -47,6 +47,7 @@
 #include "src/core/ext/client_channel/lb_policy_registry.h"
 #include "src/core/ext/client_channel/proxy_mapper_registry.h"
 #include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/client_channel/retry_throttle.h"
 #include "src/core/ext/client_channel/subchannel.h"
 #include "src/core/lib/channel/channel_args.h"
 #include "src/core/lib/channel/connected_channel.h"
@@ -189,6 +190,8 @@ typedef struct client_channel_channel_data {
   grpc_combiner *combiner;
   /** currently active load balancer */
   grpc_lb_policy *lb_policy;
+  /** retry throttle data */
+  grpc_server_retry_throttle_data *retry_throttle_data;
   /** maps method names to method_parameters structs */
   grpc_slice_hash_table *method_params_table;
   /** incoming resolver result - set by resolver.next() */
@@ -284,6 +287,65 @@ static void watch_lb_policy_locked(grpc_exec_ctx *exec_ctx, channel_data *chand,
                                                &w->on_changed);
 }
 
+typedef struct {
+  char *server_name;
+  grpc_server_retry_throttle_data *retry_throttle_data;
+} service_config_parsing_state;
+
+static void parse_retry_throttle_params(const grpc_json *field, void *arg) {
+  service_config_parsing_state *parsing_state = arg;
+  if (strcmp(field->key, "retryThrottling") == 0) {
+    if (parsing_state->retry_throttle_data != NULL) return;  // Duplicate.
+    if (field->type != GRPC_JSON_OBJECT) return;
+    int max_milli_tokens = 0;
+    int milli_token_ratio = 0;
+    for (grpc_json *sub_field = field->child; sub_field != NULL;
+         sub_field = sub_field->next) {
+      if (sub_field->key == NULL) return;
+      if (strcmp(sub_field->key, "maxTokens") == 0) {
+        if (max_milli_tokens != 0) return;  // Duplicate.
+        if (sub_field->type != GRPC_JSON_NUMBER) return;
+        max_milli_tokens = gpr_parse_nonnegative_int(sub_field->value);
+        if (max_milli_tokens == -1) return;
+        max_milli_tokens *= 1000;
+      } else if (strcmp(sub_field->key, "tokenRatio") == 0) {
+        if (milli_token_ratio != 0) return;  // Duplicate.
+        if (sub_field->type != GRPC_JSON_NUMBER) return;
+        // We support up to 3 decimal digits.
+        size_t whole_len = strlen(sub_field->value);
+        uint32_t multiplier = 1;
+        uint32_t decimal_value = 0;
+        const char *decimal_point = strchr(sub_field->value, '.');
+        if (decimal_point != NULL) {
+          whole_len = (size_t)(decimal_point - sub_field->value);
+          multiplier = 1000;
+          size_t decimal_len = strlen(decimal_point + 1);
+          if (decimal_len > 3) decimal_len = 3;
+          if (!gpr_parse_bytes_to_uint32(decimal_point + 1, decimal_len,
+                                         &decimal_value)) {
+            return;
+          }
+          uint32_t decimal_multiplier = 1;
+          for (size_t i = 0; i < (3 - decimal_len); ++i) {
+            decimal_multiplier *= 10;
+          }
+          decimal_value *= decimal_multiplier;
+        }
+        uint32_t whole_value;
+        if (!gpr_parse_bytes_to_uint32(sub_field->value, whole_len,
+                                       &whole_value)) {
+          return;
+        }
+        milli_token_ratio = (int)((whole_value * multiplier) + decimal_value);
+        if (milli_token_ratio <= 0) return;
+      }
+    }
+    parsing_state->retry_throttle_data =
+        grpc_retry_throttle_map_get_data_for_server(
+            parsing_state->server_name, max_milli_tokens, milli_token_ratio);
+  }
+}
+
 static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
                                               void *arg, grpc_error *error) {
   channel_data *chand = arg;
@@ -293,8 +355,11 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
   grpc_slice_hash_table *method_params_table = NULL;
   grpc_connectivity_state state = GRPC_CHANNEL_TRANSIENT_FAILURE;
   bool exit_idle = false;
-  grpc_error *state_error = GRPC_ERROR_CREATE("No load balancing policy");
+  grpc_error *state_error =
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("No load balancing policy");
   char *service_config_json = NULL;
+  service_config_parsing_state parsing_state;
+  memset(&parsing_state, 0, sizeof(parsing_state));
 
   if (chand->resolver_result != NULL) {
     // Find LB policy name.
@@ -355,6 +420,19 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
       grpc_service_config *service_config =
           grpc_service_config_create(service_config_json);
       if (service_config != NULL) {
+        channel_arg =
+            grpc_channel_args_find(chand->resolver_result, GRPC_ARG_SERVER_URI);
+        GPR_ASSERT(channel_arg != NULL);
+        GPR_ASSERT(channel_arg->type == GRPC_ARG_STRING);
+        grpc_uri *uri =
+            grpc_uri_parse(exec_ctx, channel_arg->value.string, true);
+        GPR_ASSERT(uri->path[0] != '\0');
+        parsing_state.server_name =
+            uri->path[0] == '/' ? uri->path + 1 : uri->path;
+        grpc_service_config_parse_global_params(
+            service_config, parse_retry_throttle_params, &parsing_state);
+        parsing_state.server_name = NULL;
+        grpc_uri_destroy(uri);
         method_params_table = grpc_service_config_create_method_config_table(
             exec_ctx, service_config, method_parameters_create_from_json,
             &method_parameters_vtable);
@@ -386,6 +464,11 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     chand->info_service_config_json = service_config_json;
   }
   gpr_mu_unlock(&chand->info_mu);
+
+  if (chand->retry_throttle_data != NULL) {
+    grpc_server_retry_throttle_data_unref(chand->retry_throttle_data);
+  }
+  chand->retry_throttle_data = parsing_state.retry_throttle_data;
   if (chand->method_params_table != NULL) {
     grpc_slice_hash_table_unref(exec_ctx, chand->method_params_table);
   }
@@ -393,9 +476,9 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
   if (lb_policy != NULL) {
     grpc_closure_list_sched(exec_ctx, &chand->waiting_for_config_closures);
   } else if (chand->resolver == NULL /* disconnected */) {
-    grpc_closure_list_fail_all(
-        &chand->waiting_for_config_closures,
-        GRPC_ERROR_CREATE_REFERENCING("Channel disconnected", &error, 1));
+    grpc_closure_list_fail_all(&chand->waiting_for_config_closures,
+                               GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                                   "Channel disconnected", &error, 1));
     grpc_closure_list_sched(exec_ctx, &chand->waiting_for_config_closures);
   }
   if (lb_policy != NULL && chand->exit_idle_when_lb_policy_arrives) {
@@ -423,8 +506,8 @@ static void on_resolver_result_changed_locked(grpc_exec_ctx *exec_ctx,
     grpc_error *refs[] = {error, state_error};
     set_channel_connectivity_state_locked(
         exec_ctx, chand, GRPC_CHANNEL_SHUTDOWN,
-        GRPC_ERROR_CREATE_REFERENCING("Got config after disconnection", refs,
-                                      GPR_ARRAY_SIZE(refs)),
+        GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+            "Got config after disconnection", refs, GPR_ARRAY_SIZE(refs)),
         "resolver_gone");
   }
 
@@ -463,8 +546,9 @@ static void start_transport_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
 
   if (op->send_ping != NULL) {
     if (chand->lb_policy == NULL) {
-      grpc_closure_sched(exec_ctx, op->send_ping,
-                         GRPC_ERROR_CREATE("Ping with no load balancing"));
+      grpc_closure_sched(
+          exec_ctx, op->send_ping,
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Ping with no load balancing"));
     } else {
       grpc_lb_policy_ping_one_locked(exec_ctx, chand->lb_policy, op->send_ping);
       op->bind_pollset = NULL;
@@ -579,7 +663,7 @@ static grpc_error *cc_init_channel_elem(grpc_exec_ctx *exec_ctx,
   if (proxy_name != NULL) gpr_free(proxy_name);
   if (new_args != NULL) grpc_channel_args_destroy(exec_ctx, new_args);
   if (chand->resolver == NULL) {
-    return GRPC_ERROR_CREATE("resolver creation failed");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("resolver creation failed");
   }
   return GRPC_ERROR_NONE;
 }
@@ -613,6 +697,9 @@ static void cc_destroy_channel_elem(grpc_exec_ctx *exec_ctx,
   }
   gpr_free(chand->info_lb_policy_name);
   gpr_free(chand->info_service_config_json);
+  if (chand->retry_throttle_data != NULL) {
+    grpc_server_retry_throttle_data_unref(chand->retry_throttle_data);
+  }
   if (chand->method_params_table != NULL) {
     grpc_slice_hash_table_unref(exec_ctx, chand->method_params_table);
   }
@@ -654,6 +741,7 @@ typedef struct client_channel_call_data {
   grpc_slice path;  // Request path.
   gpr_timespec call_start_time;
   gpr_timespec deadline;
+  grpc_server_retry_throttle_data *retry_throttle_data;
   method_parameters *method_params;
 
   grpc_error *cancel_error;
@@ -676,6 +764,9 @@ typedef struct client_channel_call_data {
   grpc_call_stack *owning_call;
 
   grpc_linked_mdelem lb_token_mdelem;
+
+  grpc_closure on_complete;
+  grpc_closure *original_on_complete;
 } call_data;
 
 grpc_subchannel_call *grpc_client_channel_get_subchannel_call(
@@ -728,7 +819,7 @@ static void retry_waiting_locked(grpc_exec_ctx *exec_ctx, call_data *calld) {
   gpr_free(ops);
 }
 
-// Sets calld->method_params.
+// Sets calld->method_params and calld->retry_throttle_data.
 // If the method params specify a timeout, populates
 // *per_method_deadline and returns true.
 static bool set_call_method_params_from_service_config_locked(
@@ -736,6 +827,10 @@ static bool set_call_method_params_from_service_config_locked(
     gpr_timespec *per_method_deadline) {
   channel_data *chand = elem->channel_data;
   call_data *calld = elem->call_data;
+  if (chand->retry_throttle_data != NULL) {
+    calld->retry_throttle_data =
+        grpc_server_retry_throttle_data_ref(chand->retry_throttle_data);
+  }
   if (chand->method_params_table != NULL) {
     calld->method_params = grpc_method_config_table_get(
         exec_ctx, chand->method_params_table, calld->path);
@@ -781,12 +876,14 @@ static void subchannel_ready_locked(grpc_exec_ctx *exec_ctx, void *arg,
   calld->creation_phase = GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING;
   if (calld->connected_subchannel == NULL) {
     gpr_atm_no_barrier_store(&calld->subchannel_call, 1);
-    fail_locked(exec_ctx, calld, GRPC_ERROR_CREATE_REFERENCING(
-                                     "Failed to create subchannel", &error, 1));
+    fail_locked(exec_ctx, calld,
+                GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                    "Failed to create subchannel", &error, 1));
   } else if (GET_CALL(calld) == CANCELLED_CALL) {
     /* already cancelled before subchannel became ready */
-    grpc_error *cancellation_error = GRPC_ERROR_CREATE_REFERENCING(
-        "Cancelled before creating subchannel", &error, 1);
+    grpc_error *cancellation_error =
+        GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+            "Cancelled before creating subchannel", &error, 1);
     /* if due to deadline, attach the deadline exceeded status to the error */
     if (gpr_time_cmp(calld->deadline, gpr_now(GPR_CLOCK_MONOTONIC)) < 0) {
       cancellation_error =
@@ -888,9 +985,9 @@ static bool pick_subchannel_locked(
       cpa = closure->cb_arg;
       if (cpa->connected_subchannel == connected_subchannel) {
         cpa->connected_subchannel = NULL;
-        grpc_closure_sched(
-            exec_ctx, cpa->on_ready,
-            GRPC_ERROR_CREATE_REFERENCING("Pick cancelled", &error, 1));
+        grpc_closure_sched(exec_ctx, cpa->on_ready,
+                           GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                               "Pick cancelled", &error, 1));
       }
     }
     GPR_TIMER_END("pick_subchannel", 0);
@@ -947,7 +1044,8 @@ static bool pick_subchannel_locked(
     grpc_closure_list_append(&chand->waiting_for_config_closures, &cpa->closure,
                              GRPC_ERROR_NONE);
   } else {
-    grpc_closure_sched(exec_ctx, on_ready, GRPC_ERROR_CREATE("Disconnected"));
+    grpc_closure_sched(exec_ctx, on_ready,
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Disconnected"));
   }
 
   GPR_TIMER_END("pick_subchannel", 0);
@@ -1056,6 +1154,26 @@ static void start_transport_stream_op_locked_inner(grpc_exec_ctx *exec_ctx,
   add_waiting_locked(calld, op);
 }
 
+static void on_complete(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
+  grpc_call_element *elem = arg;
+  call_data *calld = elem->call_data;
+  if (calld->retry_throttle_data != NULL) {
+    if (error == GRPC_ERROR_NONE) {
+      grpc_server_retry_throttle_data_record_success(
+          calld->retry_throttle_data);
+    } else {
+      // TODO(roth): In a subsequent PR, check the return value here and
+      // decide whether or not to retry.  Note that we should only
+      // record failures whose statuses match the configured retryable
+      // or non-fatal status codes.
+      grpc_server_retry_throttle_data_record_failure(
+          calld->retry_throttle_data);
+    }
+  }
+  grpc_closure_run(exec_ctx, calld->original_on_complete,
+                   GRPC_ERROR_REF(error));
+}
+
 static void start_transport_stream_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
                                              grpc_error *error_ignored) {
   GPR_TIMER_BEGIN("start_transport_stream_op_locked", 0);
@@ -1064,6 +1182,14 @@ static void start_transport_stream_op_locked(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_call_element *elem = op->handler_private.args[0];
   call_data *calld = elem->call_data;
 
+  if (op->recv_trailing_metadata != NULL) {
+    GPR_ASSERT(op->on_complete != NULL);
+    calld->original_on_complete = op->on_complete;
+    grpc_closure_init(&calld->on_complete, on_complete, elem,
+                      grpc_schedule_on_exec_ctx);
+    op->on_complete = &calld->on_complete;
+  }
+
   start_transport_stream_op_locked_inner(exec_ctx, op, elem);
 
   GRPC_CALL_STACK_UNREF(exec_ctx, calld->owning_call,
diff --git a/src/core/ext/client_channel/client_channel_plugin.c b/src/core/ext/client_channel/client_channel_plugin.c
index 28d3b63f99..f51277d0b2 100644
--- a/src/core/ext/client_channel/client_channel_plugin.c
+++ b/src/core/ext/client_channel/client_channel_plugin.c
@@ -43,6 +43,7 @@
 #include "src/core/ext/client_channel/lb_policy_registry.h"
 #include "src/core/ext/client_channel/proxy_mapper_registry.h"
 #include "src/core/ext/client_channel/resolver_registry.h"
+#include "src/core/ext/client_channel/retry_throttle.h"
 #include "src/core/ext/client_channel/subchannel_index.h"
 #include "src/core/lib/surface/channel_init.h"
 
@@ -82,6 +83,7 @@ static bool set_default_host_if_unset(grpc_exec_ctx *exec_ctx,
 void grpc_client_channel_init(void) {
   grpc_lb_policy_registry_init();
   grpc_resolver_registry_init();
+  grpc_retry_throttle_map_init();
   grpc_proxy_mapper_registry_init();
   grpc_register_http_proxy_mapper();
   grpc_subchannel_index_init();
@@ -96,6 +98,7 @@ void grpc_client_channel_shutdown(void) {
   grpc_subchannel_index_shutdown();
   grpc_channel_init_shutdown();
   grpc_proxy_mapper_registry_shutdown();
+  grpc_retry_throttle_map_shutdown();
   grpc_resolver_registry_shutdown();
   grpc_lb_policy_registry_shutdown();
 }
diff --git a/src/core/ext/client_channel/connector.h b/src/core/ext/client_channel/connector.h
index 9bff41f003..94b5fb5c9e 100644
--- a/src/core/ext/client_channel/connector.h
+++ b/src/core/ext/client_channel/connector.h
@@ -48,8 +48,6 @@ struct grpc_connector {
 typedef struct {
   /** set of pollsets interested in this connection */
   grpc_pollset_set *interested_parties;
-  /** initial connect string to send */
-  grpc_slice initial_connect_string;
   /** deadline for connection */
   gpr_timespec deadline;
   /** channel arguments (to be passed to transport) */
diff --git a/src/core/ext/client_channel/http_connect_handshaker.c b/src/core/ext/client_channel/http_connect_handshaker.c
index 58ab233f1b..778d76c39f 100644
--- a/src/core/ext/client_channel/http_connect_handshaker.c
+++ b/src/core/ext/client_channel/http_connect_handshaker.c
@@ -116,7 +116,7 @@ static void handshake_failed_locked(grpc_exec_ctx* exec_ctx,
     // If we were shut down after an endpoint operation succeeded but
     // before the endpoint callback was invoked, we need to generate our
     // own error.
-    error = GRPC_ERROR_CREATE("Handshaker shutdown");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshaker shutdown");
   }
   if (!handshaker->shutdown) {
     // TODO(ctiller): It is currently necessary to shutdown endpoints
@@ -226,7 +226,7 @@ static void on_read_done(grpc_exec_ctx* exec_ctx, void* arg,
     char* msg;
     gpr_asprintf(&msg, "HTTP proxy returned response code %d",
                  handshaker->http_response.status);
-    error = GRPC_ERROR_CREATE(msg);
+    error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     handshake_failed_locked(exec_ctx, handshaker, error);
     goto done;
diff --git a/src/core/ext/client_channel/initial_connect_string.h b/src/core/ext/client_channel/initial_connect_string.h
deleted file mode 100644
index 876abea40e..0000000000
--- a/src/core/ext/client_channel/initial_connect_string.h
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
- *
- * Copyright 2015, Google Inc.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are
- * met:
- *
- *     * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- *     * Redistributions in binary form must reproduce the above
- * copyright notice, this list of conditions and the following disclaimer
- * in the documentation and/or other materials provided with the
- * distribution.
- *     * Neither the name of Google Inc. nor the names of its
- * contributors may be used to endorse or promote products derived from
- * this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_INITIAL_CONNECT_STRING_H
-#define GRPC_CORE_EXT_CLIENT_CHANNEL_INITIAL_CONNECT_STRING_H
-
-#include <grpc/slice.h>
-#include "src/core/lib/iomgr/resolve_address.h"
-
-typedef void (*grpc_set_initial_connect_string_func)(
-    grpc_resolved_address **addr, grpc_slice *initial_str);
-
-void grpc_test_set_initial_connect_string_function(
-    grpc_set_initial_connect_string_func func);
-
-/** Set a string to be sent once connected. Optionally reset addr. */
-void grpc_set_initial_connect_string(grpc_resolved_address **addr,
-                                     grpc_slice *connect_string);
-
-#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_INITIAL_CONNECT_STRING_H */
diff --git a/src/core/ext/client_channel/retry_throttle.c b/src/core/ext/client_channel/retry_throttle.c
new file mode 100644
index 0000000000..8926c3d782
--- /dev/null
+++ b/src/core/ext/client_channel/retry_throttle.c
@@ -0,0 +1,210 @@
+/*
+ *
+ * Copyright 2017, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "src/core/ext/client_channel/retry_throttle.h"
+
+#include <limits.h>
+#include <string.h>
+
+#include <grpc/support/alloc.h>
+#include <grpc/support/atm.h>
+#include <grpc/support/avl.h>
+#include <grpc/support/string_util.h>
+#include <grpc/support/sync.h>
+
+//
+// server_retry_throttle_data
+//
+
+struct grpc_server_retry_throttle_data {
+  gpr_refcount refs;
+  int max_milli_tokens;
+  int milli_token_ratio;
+  gpr_atm milli_tokens;
+  // A pointer to the replacement for this grpc_server_retry_throttle_data
+  // entry.  If non-NULL, then this entry is stale and must not be used.
+  // We hold a reference to the replacement.
+  gpr_atm replacement;
+};
+
+static void get_replacement_throttle_data_if_needed(
+    grpc_server_retry_throttle_data** throttle_data) {
+  while (true) {
+    grpc_server_retry_throttle_data* new_throttle_data =
+        (grpc_server_retry_throttle_data*)gpr_atm_acq_load(
+            &(*throttle_data)->replacement);
+    if (new_throttle_data == NULL) return;
+    *throttle_data = new_throttle_data;
+  }
+}
+
+bool grpc_server_retry_throttle_data_record_failure(
+    grpc_server_retry_throttle_data* throttle_data) {
+  // First, check if we are stale and need to be replaced.
+  get_replacement_throttle_data_if_needed(&throttle_data);
+  // We decrement milli_tokens by 1000 (1 token) for each failure.
+  const int new_value = (int)gpr_atm_no_barrier_clamped_add(
+      &throttle_data->milli_tokens, (gpr_atm)-1000, (gpr_atm)0,
+      (gpr_atm)throttle_data->max_milli_tokens);
+  // Retries are allowed as long as the new value is above the threshold
+  // (max_milli_tokens / 2).
+  return new_value > throttle_data->max_milli_tokens / 2;
+}
+
+void grpc_server_retry_throttle_data_record_success(
+    grpc_server_retry_throttle_data* throttle_data) {
+  // First, check if we are stale and need to be replaced.
+  get_replacement_throttle_data_if_needed(&throttle_data);
+  // We increment milli_tokens by milli_token_ratio for each success.
+  gpr_atm_no_barrier_clamped_add(
+      &throttle_data->milli_tokens, (gpr_atm)throttle_data->milli_token_ratio,
+      (gpr_atm)0, (gpr_atm)throttle_data->max_milli_tokens);
+}
+
+grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_ref(
+    grpc_server_retry_throttle_data* throttle_data) {
+  gpr_ref(&throttle_data->refs);
+  return throttle_data;
+}
+
+void grpc_server_retry_throttle_data_unref(
+    grpc_server_retry_throttle_data* throttle_data) {
+  if (gpr_unref(&throttle_data->refs)) {
+    grpc_server_retry_throttle_data* replacement =
+        (grpc_server_retry_throttle_data*)gpr_atm_acq_load(
+            &throttle_data->replacement);
+    if (replacement != NULL) {
+      grpc_server_retry_throttle_data_unref(replacement);
+    }
+    gpr_free(throttle_data);
+  }
+}
+
+static grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_create(
+    int max_milli_tokens, int milli_token_ratio,
+    grpc_server_retry_throttle_data* old_throttle_data) {
+  grpc_server_retry_throttle_data* throttle_data =
+      gpr_malloc(sizeof(*throttle_data));
+  memset(throttle_data, 0, sizeof(*throttle_data));
+  gpr_ref_init(&throttle_data->refs, 1);
+  throttle_data->max_milli_tokens = max_milli_tokens;
+  throttle_data->milli_token_ratio = milli_token_ratio;
+  int initial_milli_tokens = max_milli_tokens;
+  // If there was a pre-existing entry for this server name, initialize
+  // the token count by scaling proportionately to the old data.  This
+  // ensures that if we're already throttling retries on the old scale,
+  // we will start out doing the same thing on the new one.
+  if (old_throttle_data != NULL) {
+    double token_fraction =
+        (int)gpr_atm_acq_load(&old_throttle_data->milli_tokens) /
+        (double)old_throttle_data->max_milli_tokens;
+    initial_milli_tokens = (int)(token_fraction * max_milli_tokens);
+  }
+  gpr_atm_rel_store(&throttle_data->milli_tokens,
+                    (gpr_atm)initial_milli_tokens);
+  // If there was a pre-existing entry, mark it as stale and give it a
+  // pointer to the new entry, which is its replacement.
+  if (old_throttle_data != NULL) {
+    grpc_server_retry_throttle_data_ref(throttle_data);
+    gpr_atm_rel_store(&old_throttle_data->replacement, (gpr_atm)throttle_data);
+  }
+  return throttle_data;
+}
+
+//
+// avl vtable for string -> server_retry_throttle_data map
+//
+
+static void* copy_server_name(void* key) { return gpr_strdup(key); }
+
+static long compare_server_name(void* key1, void* key2) {
+  return strcmp(key1, key2);
+}
+
+static void destroy_server_retry_throttle_data(void* value) {
+  grpc_server_retry_throttle_data* throttle_data = value;
+  grpc_server_retry_throttle_data_unref(throttle_data);
+}
+
+static void* copy_server_retry_throttle_data(void* value) {
+  grpc_server_retry_throttle_data* throttle_data = value;
+  return grpc_server_retry_throttle_data_ref(throttle_data);
+}
+
+static const gpr_avl_vtable avl_vtable = {
+    gpr_free /* destroy_key */, copy_server_name, compare_server_name,
+    destroy_server_retry_throttle_data, copy_server_retry_throttle_data};
+
+//
+// server_retry_throttle_map
+//
+
+static gpr_mu g_mu;
+static gpr_avl g_avl;
+
+void grpc_retry_throttle_map_init() {
+  gpr_mu_init(&g_mu);
+  g_avl = gpr_avl_create(&avl_vtable);
+}
+
+void grpc_retry_throttle_map_shutdown() {
+  gpr_mu_destroy(&g_mu);
+  gpr_avl_unref(g_avl);
+}
+
+grpc_server_retry_throttle_data* grpc_retry_throttle_map_get_data_for_server(
+    const char* server_name, int max_milli_tokens, int milli_token_ratio) {
+  gpr_mu_lock(&g_mu);
+  grpc_server_retry_throttle_data* throttle_data =
+      gpr_avl_get(g_avl, (char*)server_name);
+  if (throttle_data == NULL) {
+    // Entry not found.  Create a new one.
+    throttle_data = grpc_server_retry_throttle_data_create(
+        max_milli_tokens, milli_token_ratio, NULL);
+    g_avl = gpr_avl_add(g_avl, (char*)server_name, throttle_data);
+  } else {
+    if (throttle_data->max_milli_tokens != max_milli_tokens ||
+        throttle_data->milli_token_ratio != milli_token_ratio) {
+      // Entry found but with old parameters.  Create a new one based on
+      // the original one.
+      throttle_data = grpc_server_retry_throttle_data_create(
+          max_milli_tokens, milli_token_ratio, throttle_data);
+      g_avl = gpr_avl_add(g_avl, (char*)server_name, throttle_data);
+    } else {
+      // Entry found.  Increase refcount.
+      grpc_server_retry_throttle_data_ref(throttle_data);
+    }
+  }
+  gpr_mu_unlock(&g_mu);
+  return throttle_data;
+}
diff --git a/src/core/ext/client_channel/initial_connect_string.c b/src/core/ext/client_channel/retry_throttle.h
index 8ebd06c458..f9971faf65 100644
--- a/src/core/ext/client_channel/initial_connect_string.c
+++ b/src/core/ext/client_channel/retry_throttle.h
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2017, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -31,22 +31,35 @@
  *
  */
 
-#include "src/core/ext/client_channel/initial_connect_string.h"
+#ifndef GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H
+#define GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H
 
-#include <stddef.h>
+#include <stdbool.h>
 
-extern void grpc_set_default_initial_connect_string(
-    grpc_resolved_address **addr, grpc_slice *initial_str);
+/// Tracks retry throttling data for an individual server name.
+typedef struct grpc_server_retry_throttle_data grpc_server_retry_throttle_data;
 
-static grpc_set_initial_connect_string_func g_set_initial_connect_string_func =
-    grpc_set_default_initial_connect_string;
+/// Records a failure.  Returns true if it's okay to send a retry.
+bool grpc_server_retry_throttle_data_record_failure(
+    grpc_server_retry_throttle_data* throttle_data);
+/// Records a success.
+void grpc_server_retry_throttle_data_record_success(
+    grpc_server_retry_throttle_data* throttle_data);
 
-void grpc_test_set_initial_connect_string_function(
-    grpc_set_initial_connect_string_func func) {
-  g_set_initial_connect_string_func = func;
-}
+grpc_server_retry_throttle_data* grpc_server_retry_throttle_data_ref(
+    grpc_server_retry_throttle_data* throttle_data);
+void grpc_server_retry_throttle_data_unref(
+    grpc_server_retry_throttle_data* throttle_data);
 
-void grpc_set_initial_connect_string(grpc_resolved_address **addr,
-                                     grpc_slice *initial_str) {
-  g_set_initial_connect_string_func(addr, initial_str);
-}
+/// Initializes global map of failure data for each server name.
+void grpc_retry_throttle_map_init();
+/// Shuts down global map of failure data for each server name.
+void grpc_retry_throttle_map_shutdown();
+
+/// Returns a reference to the failure data for \a server_name, creating
+/// a new entry if needed.
+/// Caller must eventually unref via \a grpc_server_retry_throttle_data_unref().
+grpc_server_retry_throttle_data* grpc_retry_throttle_map_get_data_for_server(
+    const char* server_name, int max_milli_tokens, int milli_token_ratio);
+
+#endif /* GRPC_CORE_EXT_CLIENT_CHANNEL_RETRY_THROTTLE_H */
diff --git a/src/core/ext/client_channel/subchannel.c b/src/core/ext/client_channel/subchannel.c
index ed5029ea9a..063c0badff 100644
--- a/src/core/ext/client_channel/subchannel.c
+++ b/src/core/ext/client_channel/subchannel.c
@@ -41,7 +41,6 @@
 #include <grpc/support/string_util.h>
 
 #include "src/core/ext/client_channel/client_channel.h"
-#include "src/core/ext/client_channel/initial_connect_string.h"
 #include "src/core/ext/client_channel/parse_address.h"
 #include "src/core/ext/client_channel/proxy_mapper_registry.h"
 #include "src/core/ext/client_channel/subchannel_index.h"
@@ -103,9 +102,6 @@ struct grpc_subchannel {
 
   grpc_subchannel_key *key;
 
-  /** initial string to send to peer */
-  grpc_slice initial_connect_string;
-
   /** set during connection */
   grpc_connect_out_args connecting_result;
 
@@ -215,7 +211,6 @@ static void subchannel_destroy(grpc_exec_ctx *exec_ctx, void *arg,
   grpc_subchannel *c = arg;
   gpr_free((void *)c->filters);
   grpc_channel_args_destroy(exec_ctx, c->args);
-  grpc_slice_unref_internal(exec_ctx, c->initial_connect_string);
   grpc_connectivity_state_destroy(exec_ctx, &c->state_tracker);
   grpc_connector_unref(exec_ctx, c->connector);
   grpc_pollset_set_destroy(exec_ctx, c->pollset_set);
@@ -274,8 +269,9 @@ static void disconnect(grpc_exec_ctx *exec_ctx, grpc_subchannel *c) {
   gpr_mu_lock(&c->mu);
   GPR_ASSERT(!c->disconnected);
   c->disconnected = true;
-  grpc_connector_shutdown(exec_ctx, c->connector,
-                          GRPC_ERROR_CREATE("Subchannel disconnected"));
+  grpc_connector_shutdown(
+      exec_ctx, c->connector,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Subchannel disconnected"));
   con = GET_CONNECTED_SUBCHANNEL(c, no_barrier);
   if (con != NULL) {
     GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, con, "connection");
@@ -333,7 +329,6 @@ grpc_subchannel *grpc_subchannel_create(grpc_exec_ctx *exec_ctx,
   c->pollset_set = grpc_pollset_set_create();
   grpc_resolved_address *addr = gpr_malloc(sizeof(*addr));
   grpc_get_subchannel_address_arg(exec_ctx, args->args, addr);
-  grpc_set_initial_connect_string(&addr, &c->initial_connect_string);
   grpc_resolved_address *new_address = NULL;
   grpc_channel_args *new_args = NULL;
   if (grpc_proxy_mappers_map_address(exec_ctx, addr, args->args, &new_address,
@@ -404,7 +399,6 @@ static void continue_connect_locked(grpc_exec_ctx *exec_ctx,
   args.interested_parties = c->pollset_set;
   args.deadline = c->next_attempt;
   args.channel_args = c->args;
-  args.initial_connect_string = c->initial_connect_string;
 
   grpc_connectivity_state_set(exec_ctx, &c->state_tracker,
                               GRPC_CHANNEL_CONNECTING, GRPC_ERROR_NONE,
@@ -444,7 +438,8 @@ static void on_alarm(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
   gpr_mu_lock(&c->mu);
   c->have_alarm = false;
   if (c->disconnected) {
-    error = GRPC_ERROR_CREATE_REFERENCING("Disconnected", &error, 1);
+    error = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING("Disconnected",
+                                                             &error, 1);
   } else {
     GRPC_ERROR_REF(error);
   }
@@ -695,9 +690,9 @@ static void subchannel_connected(grpc_exec_ctx *exec_ctx, void *arg,
   } else {
     grpc_connectivity_state_set(
         exec_ctx, &c->state_tracker, GRPC_CHANNEL_TRANSIENT_FAILURE,
-        grpc_error_set_int(
-            GRPC_ERROR_CREATE_REFERENCING("Connect Failed", &error, 1),
-            GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAVAILABLE),
+        grpc_error_set_int(GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                               "Connect Failed", &error, 1),
+                           GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAVAILABLE),
         "connect_failed");
 
     const char *errmsg = grpc_error_string(error);
diff --git a/src/core/ext/lb_policy/grpclb/grpclb.c b/src/core/ext/lb_policy/grpclb/grpclb.c
index d612591f2e..601b0e643b 100644
--- a/src/core/ext/lb_policy/grpclb/grpclb.c
+++ b/src/core/ext/lb_policy/grpclb/grpclb.c
@@ -925,7 +925,7 @@ static void glb_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   }
   grpc_connectivity_state_set(
       exec_ctx, &glb_policy->state_tracker, GRPC_CHANNEL_SHUTDOWN,
-      GRPC_ERROR_CREATE("Channel Shutdown"), "glb_shutdown");
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Shutdown"), "glb_shutdown");
   /* We need a copy of the lb_call pointer because we can't cancell the call
    * while holding glb_policy->mu: lb_on_server_status_received, invoked due to
    * the cancel, needs to acquire that same lock */
@@ -965,9 +965,9 @@ static void glb_cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if (pp->target == target) {
       *target = NULL;
-      grpc_closure_sched(
-          exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
-          GRPC_ERROR_CREATE_REFERENCING("Pick Cancelled", &error, 1));
+      grpc_closure_sched(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
+                         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                             "Pick Cancelled", &error, 1));
     } else {
       pp->next = glb_policy->pending_picks;
       glb_policy->pending_picks = pp;
@@ -989,9 +989,9 @@ static void glb_cancel_picks_locked(grpc_exec_ctx *exec_ctx,
     pending_pick *next = pp->next;
     if ((pp->pick_args.initial_metadata_flags & initial_metadata_flags_mask) ==
         initial_metadata_flags_eq) {
-      grpc_closure_sched(
-          exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
-          GRPC_ERROR_CREATE_REFERENCING("Pick Cancelled", &error, 1));
+      grpc_closure_sched(exec_ctx, &pp->wrapped_on_complete_arg.wrapper_closure,
+                         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                             "Pick Cancelled", &error, 1));
     } else {
       pp->next = glb_policy->pending_picks;
       glb_policy->pending_picks = pp;
@@ -1023,10 +1023,10 @@ static int glb_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
                            grpc_closure *on_complete) {
   if (pick_args->lb_token_mdelem_storage == NULL) {
     *target = NULL;
-    grpc_closure_sched(
-        exec_ctx, on_complete,
-        GRPC_ERROR_CREATE("No mdelem storage for the LB token. Load reporting "
-                          "won't work without it. Failing"));
+    grpc_closure_sched(exec_ctx, on_complete,
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                           "No mdelem storage for the LB token. Load reporting "
+                           "won't work without it. Failing"));
     return 0;
   }
 
diff --git a/src/core/ext/lb_policy/pick_first/pick_first.c b/src/core/ext/lb_policy/pick_first/pick_first.c
index e2a66d16bd..fc65dfdcb9 100644
--- a/src/core/ext/lb_policy/pick_first/pick_first.c
+++ b/src/core/ext/lb_policy/pick_first/pick_first.c
@@ -101,7 +101,7 @@ static void pf_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   p->pending_picks = NULL;
   grpc_connectivity_state_set(
       exec_ctx, &p->state_tracker, GRPC_CHANNEL_SHUTDOWN,
-      GRPC_ERROR_CREATE("Channel shutdown"), "shutdown");
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel shutdown"), "shutdown");
   /* cancel subscription */
   if (p->selected != NULL) {
     grpc_connected_subchannel_notify_on_state_change(
@@ -131,9 +131,9 @@ static void pf_cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if (pp->target == target) {
       *target = NULL;
-      grpc_closure_sched(
-          exec_ctx, pp->on_complete,
-          GRPC_ERROR_CREATE_REFERENCING("Pick Cancelled", &error, 1));
+      grpc_closure_sched(exec_ctx, pp->on_complete,
+                         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                             "Pick Cancelled", &error, 1));
       gpr_free(pp);
     } else {
       pp->next = p->pending_picks;
@@ -156,9 +156,9 @@ static void pf_cancel_picks_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if ((pp->initial_metadata_flags & initial_metadata_flags_mask) ==
         initial_metadata_flags_eq) {
-      grpc_closure_sched(
-          exec_ctx, pp->on_complete,
-          GRPC_ERROR_CREATE_REFERENCING("Pick Cancelled", &error, 1));
+      grpc_closure_sched(exec_ctx, pp->on_complete,
+                         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                             "Pick Cancelled", &error, 1));
       gpr_free(pp);
     } else {
       pp->next = p->pending_picks;
@@ -325,8 +325,8 @@ static void pf_connectivity_changed_locked(grpc_exec_ctx *exec_ctx, void *arg,
         if (p->num_subchannels == 0) {
           grpc_connectivity_state_set(
               exec_ctx, &p->state_tracker, GRPC_CHANNEL_SHUTDOWN,
-              GRPC_ERROR_CREATE_REFERENCING("Pick first exhausted channels",
-                                            &error, 1),
+              GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                  "Pick first exhausted channels", &error, 1),
               "no_more_channels");
           while ((pp = p->pending_picks)) {
             p->pending_picks = pp->next;
@@ -373,7 +373,8 @@ static void pf_ping_one_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
   if (p->selected) {
     grpc_connected_subchannel_ping(exec_ctx, p->selected, closure);
   } else {
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_CREATE("Not connected"));
+    grpc_closure_sched(exec_ctx, closure,
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Not connected"));
   }
 }
 
@@ -423,11 +424,13 @@ static grpc_lb_policy *create_pick_first(grpc_exec_ctx *exec_ctx,
               "This LB policy doesn't support user data. It will be ignored");
     }
 
+    static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS};
     memset(&sc_args, 0, sizeof(grpc_subchannel_args));
     grpc_arg addr_arg =
         grpc_create_subchannel_address_arg(&addresses->addresses[i].address);
-    grpc_channel_args *new_args =
-        grpc_channel_args_copy_and_add(args->args, &addr_arg, 1);
+    grpc_channel_args *new_args = grpc_channel_args_copy_and_add_and_remove(
+        args->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &addr_arg,
+        1);
     gpr_free(addr_arg.value.string);
     sc_args.args = new_args;
     grpc_subchannel *subchannel = grpc_client_channel_factory_create_subchannel(
diff --git a/src/core/ext/lb_policy/round_robin/round_robin.c b/src/core/ext/lb_policy/round_robin/round_robin.c
index f2d1d46179..a62082a2ff 100644
--- a/src/core/ext/lb_policy/round_robin/round_robin.c
+++ b/src/core/ext/lb_policy/round_robin/round_robin.c
@@ -320,13 +320,14 @@ static void rr_shutdown_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol) {
   while ((pp = p->pending_picks)) {
     p->pending_picks = pp->next;
     *pp->target = NULL;
-    grpc_closure_sched(exec_ctx, pp->on_complete,
-                       GRPC_ERROR_CREATE("Channel Shutdown"));
+    grpc_closure_sched(
+        exec_ctx, pp->on_complete,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Shutdown"));
     gpr_free(pp);
   }
   grpc_connectivity_state_set(
       exec_ctx, &p->state_tracker, GRPC_CHANNEL_SHUTDOWN,
-      GRPC_ERROR_CREATE("Channel Shutdown"), "rr_shutdown");
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Shutdown"), "rr_shutdown");
   for (i = 0; i < p->num_subchannels; i++) {
     subchannel_data *sd = p->subchannels[i];
     grpc_subchannel_notify_on_state_change(exec_ctx, sd->subchannel, NULL, NULL,
@@ -345,9 +346,9 @@ static void rr_cancel_pick_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     pending_pick *next = pp->next;
     if (pp->target == target) {
       *target = NULL;
-      grpc_closure_sched(
-          exec_ctx, pp->on_complete,
-          GRPC_ERROR_CREATE_REFERENCING("Pick cancelled", &error, 1));
+      grpc_closure_sched(exec_ctx, pp->on_complete,
+                         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                             "Pick cancelled", &error, 1));
       gpr_free(pp);
     } else {
       pp->next = p->pending_picks;
@@ -371,9 +372,9 @@ static void rr_cancel_picks_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     if ((pp->initial_metadata_flags & initial_metadata_flags_mask) ==
         initial_metadata_flags_eq) {
       *pp->target = NULL;
-      grpc_closure_sched(
-          exec_ctx, pp->on_complete,
-          GRPC_ERROR_CREATE_REFERENCING("Pick cancelled", &error, 1));
+      grpc_closure_sched(exec_ctx, pp->on_complete,
+                         GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                             "Pick cancelled", &error, 1));
       gpr_free(pp);
     } else {
       pp->next = p->pending_picks;
@@ -661,8 +662,8 @@ static void rr_ping_one_locked(grpc_exec_ctx *exec_ctx, grpc_lb_policy *pol,
     grpc_connected_subchannel_ping(exec_ctx, target, closure);
     GRPC_CONNECTED_SUBCHANNEL_UNREF(exec_ctx, target, "rr_picked");
   } else {
-    grpc_closure_sched(exec_ctx, closure,
-                       GRPC_ERROR_CREATE("Round Robin not connected"));
+    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                              "Round Robin not connected"));
   }
 }
 
@@ -709,11 +710,13 @@ static grpc_lb_policy *round_robin_create(grpc_exec_ctx *exec_ctx,
     /* Skip balancer addresses, since we only know how to handle backends. */
     if (addresses->addresses[i].is_balancer) continue;
 
+    static const char *keys_to_remove[] = {GRPC_ARG_SUBCHANNEL_ADDRESS};
     memset(&sc_args, 0, sizeof(grpc_subchannel_args));
     grpc_arg addr_arg =
         grpc_create_subchannel_address_arg(&addresses->addresses[i].address);
-    grpc_channel_args *new_args =
-        grpc_channel_args_copy_and_add(args->args, &addr_arg, 1);
+    grpc_channel_args *new_args = grpc_channel_args_copy_and_add_and_remove(
+        args->args, keys_to_remove, GPR_ARRAY_SIZE(keys_to_remove), &addr_arg,
+        1);
     gpr_free(addr_arg.value.string);
     sc_args.args = new_args;
     grpc_subchannel *subchannel = grpc_client_channel_factory_create_subchannel(
diff --git a/src/core/ext/load_reporting/load_reporting_filter.c b/src/core/ext/load_reporting/load_reporting_filter.c
index 4ed832671d..ea57c85c3a 100644
--- a/src/core/ext/load_reporting/load_reporting_filter.c
+++ b/src/core/ext/load_reporting/load_reporting_filter.c
@@ -78,8 +78,8 @@ static void on_initial_md_ready(grpc_exec_ctx *exec_ctx, void *user_data,
           GRPC_MDVALUE(calld->recv_initial_metadata->idx.named.path->md));
       calld->have_service_method = true;
     } else {
-      err =
-          grpc_error_add_child(err, GRPC_ERROR_CREATE("Missing :path header"));
+      err = grpc_error_add_child(
+          err, GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing :path header"));
     }
     if (calld->recv_initial_metadata->idx.named.lb_token != NULL) {
       calld->initial_md_string = grpc_slice_ref_internal(
diff --git a/src/core/ext/resolver/dns/native/dns_resolver.c b/src/core/ext/resolver/dns/native/dns_resolver.c
index d227c19c43..d6cb6a95a2 100644
--- a/src/core/ext/resolver/dns/native/dns_resolver.c
+++ b/src/core/ext/resolver/dns/native/dns_resolver.c
@@ -113,8 +113,9 @@ static void dns_shutdown_locked(grpc_exec_ctx *exec_ctx,
   }
   if (r->next_completion != NULL) {
     *r->target_result = NULL;
-    grpc_closure_sched(exec_ctx, r->next_completion,
-                       GRPC_ERROR_CREATE("Resolver Shutdown"));
+    grpc_closure_sched(
+        exec_ctx, r->next_completion,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Resolver Shutdown"));
     r->next_completion = NULL;
   }
 }
diff --git a/src/core/ext/transport/chttp2/client/chttp2_connector.c b/src/core/ext/transport/chttp2/client/chttp2_connector.c
index eae0145ecc..2b226c1bf7 100644
--- a/src/core/ext/transport/chttp2/client/chttp2_connector.c
+++ b/src/core/ext/transport/chttp2/client/chttp2_connector.c
@@ -63,8 +63,6 @@ typedef struct {
   grpc_closure *notify;
   grpc_connect_in_args args;
   grpc_connect_out_args *result;
-  grpc_closure initial_string_sent;
-  grpc_slice_buffer initial_string_buffer;
 
   grpc_endpoint *endpoint;  // Non-NULL until handshaking starts.
 
@@ -82,7 +80,6 @@ static void chttp2_connector_unref(grpc_exec_ctx *exec_ctx,
                                    grpc_connector *con) {
   chttp2_connector *c = (chttp2_connector *)con;
   if (gpr_unref(&c->refs)) {
-    /* c->initial_string_buffer does not need to be destroyed */
     gpr_mu_destroy(&c->mu);
     // If handshaking is not yet in progress, destroy the endpoint.
     // Otherwise, the handshaker will do this for us.
@@ -116,7 +113,7 @@ static void on_handshake_done(grpc_exec_ctx *exec_ctx, void *arg,
   gpr_mu_lock(&c->mu);
   if (error != GRPC_ERROR_NONE || c->shutdown) {
     if (error == GRPC_ERROR_NONE) {
-      error = GRPC_ERROR_CREATE("connector shutdown");
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("connector shutdown");
       // We were shut down after handshaking completed successfully, so
       // destroy the endpoint here.
       // TODO(ctiller): It is currently necessary to shutdown endpoints
@@ -160,28 +157,6 @@ static void start_handshake_locked(grpc_exec_ctx *exec_ctx,
   c->endpoint = NULL;  // Endpoint handed off to handshake manager.
 }
 
-static void on_initial_connect_string_sent(grpc_exec_ctx *exec_ctx, void *arg,
-                                           grpc_error *error) {
-  chttp2_connector *c = arg;
-  gpr_mu_lock(&c->mu);
-  if (error != GRPC_ERROR_NONE || c->shutdown) {
-    if (error == GRPC_ERROR_NONE) {
-      error = GRPC_ERROR_CREATE("connector shutdown");
-    } else {
-      error = GRPC_ERROR_REF(error);
-    }
-    memset(c->result, 0, sizeof(*c->result));
-    grpc_closure *notify = c->notify;
-    c->notify = NULL;
-    grpc_closure_sched(exec_ctx, notify, error);
-    gpr_mu_unlock(&c->mu);
-    chttp2_connector_unref(exec_ctx, arg);
-  } else {
-    start_handshake_locked(exec_ctx, c);
-    gpr_mu_unlock(&c->mu);
-  }
-}
-
 static void connected(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
   chttp2_connector *c = arg;
   gpr_mu_lock(&c->mu);
@@ -189,7 +164,7 @@ static void connected(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
   c->connecting = false;
   if (error != GRPC_ERROR_NONE || c->shutdown) {
     if (error == GRPC_ERROR_NONE) {
-      error = GRPC_ERROR_CREATE("connector shutdown");
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("connector shutdown");
     } else {
       error = GRPC_ERROR_REF(error);
     }
@@ -204,17 +179,7 @@ static void connected(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
     chttp2_connector_unref(exec_ctx, arg);
   } else {
     GPR_ASSERT(c->endpoint != NULL);
-    if (!GRPC_SLICE_IS_EMPTY(c->args.initial_connect_string)) {
-      grpc_closure_init(&c->initial_string_sent, on_initial_connect_string_sent,
-                        c, grpc_schedule_on_exec_ctx);
-      grpc_slice_buffer_init(&c->initial_string_buffer);
-      grpc_slice_buffer_add(&c->initial_string_buffer,
-                            c->args.initial_connect_string);
-      grpc_endpoint_write(exec_ctx, c->endpoint, &c->initial_string_buffer,
-                          &c->initial_string_sent);
-    } else {
-      start_handshake_locked(exec_ctx, c);
-    }
+    start_handshake_locked(exec_ctx, c);
     gpr_mu_unlock(&c->mu);
   }
 }
diff --git a/src/core/ext/transport/chttp2/server/chttp2_server.c b/src/core/ext/transport/chttp2/server/chttp2_server.c
index 837b9fd03d..6433968ca5 100644
--- a/src/core/ext/transport/chttp2/server/chttp2_server.c
+++ b/src/core/ext/transport/chttp2/server/chttp2_server.c
@@ -256,7 +256,7 @@ grpc_error *grpc_chttp2_server_add_port(grpc_exec_ctx *exec_ctx,
     char *msg;
     gpr_asprintf(&msg, "No address added out of total %" PRIuPTR " resolved",
                  naddrs);
-    err = GRPC_ERROR_CREATE_REFERENCING(msg, errors, naddrs);
+    err = GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(msg, errors, naddrs);
     gpr_free(msg);
     goto error;
   } else if (count != naddrs) {
@@ -264,7 +264,7 @@ grpc_error *grpc_chttp2_server_add_port(grpc_exec_ctx *exec_ctx,
     gpr_asprintf(&msg, "Only %" PRIuPTR
                        " addresses added out of total %" PRIuPTR " resolved",
                  count, naddrs);
-    err = GRPC_ERROR_CREATE_REFERENCING(msg, errors, naddrs);
+    err = GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(msg, errors, naddrs);
     gpr_free(msg);
 
     const char *warning_message = grpc_error_string(err);
diff --git a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
index cb2b3f5502..88c813f3be 100644
--- a/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
+++ b/src/core/ext/transport/chttp2/server/secure/server_secure_chttp2.c
@@ -61,7 +61,7 @@ int grpc_server_add_secure_http2_port(grpc_server *server, const char *addr,
       3, (server, addr, creds));
   // Create security context.
   if (creds == NULL) {
-    err = GRPC_ERROR_CREATE(
+    err = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
         "No credentials specified for secure server port (creds==NULL)");
     goto done;
   }
@@ -72,7 +72,7 @@ int grpc_server_add_secure_http2_port(grpc_server *server, const char *addr,
     gpr_asprintf(&msg,
                  "Unable to create secure server with credentials of type %s.",
                  creds->type);
-    err = grpc_error_set_int(GRPC_ERROR_CREATE(msg),
+    err = grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg),
                              GRPC_ERROR_INT_SECURITY_STATUS, status);
     gpr_free(msg);
     goto done;
diff --git a/src/core/ext/transport/chttp2/transport/chttp2_transport.c b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
index 7d80044cfe..e928745096 100644
--- a/src/core/ext/transport/chttp2/transport/chttp2_transport.c
+++ b/src/core/ext/transport/chttp2/transport/chttp2_transport.c
@@ -187,7 +187,8 @@ static void destruct_transport(grpc_exec_ctx *exec_ctx,
 
   GRPC_COMBINER_UNREF(exec_ctx, t->combiner, "chttp2_transport");
 
-  cancel_pings(exec_ctx, t, GRPC_ERROR_CREATE("Transport destroyed"));
+  cancel_pings(exec_ctx, t,
+               GRPC_ERROR_CREATE_FROM_STATIC_STRING("Transport destroyed"));
 
   while (t->write_cb_pool) {
     grpc_chttp2_write_cb *next = t->write_cb_pool->next;
@@ -494,8 +495,9 @@ static void destroy_transport_locked(grpc_exec_ctx *exec_ctx, void *tp,
   t->destroying = 1;
   close_transport_locked(
       exec_ctx, t,
-      grpc_error_set_int(GRPC_ERROR_CREATE("Transport destroyed"),
-                         GRPC_ERROR_INT_OCCURRED_DURING_WRITE, t->write_state));
+      grpc_error_set_int(
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Transport destroyed"),
+          GRPC_ERROR_INT_OCCURRED_DURING_WRITE, t->write_state));
   GRPC_CHTTP2_UNREF_TRANSPORT(exec_ctx, t, "destroy");
 }
 
@@ -518,7 +520,8 @@ static void close_transport_locked(grpc_exec_ctx *exec_ctx,
     if (t->write_state != GRPC_CHTTP2_WRITE_STATE_IDLE) {
       if (t->close_transport_on_writes_finished == NULL) {
         t->close_transport_on_writes_finished =
-            GRPC_ERROR_CREATE("Delayed close due to in-progress write");
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                "Delayed close due to in-progress write");
       }
       t->close_transport_on_writes_finished =
           grpc_error_add_child(t->close_transport_on_writes_finished, error);
@@ -834,7 +837,8 @@ static void write_action_end_locked(grpc_exec_ctx *exec_ctx, void *tp,
   if (t->sent_goaway_state == GRPC_CHTTP2_GOAWAY_SEND_SCHEDULED) {
     t->sent_goaway_state = GRPC_CHTTP2_GOAWAY_SENT;
     if (grpc_chttp2_stream_map_size(&t->stream_map) == 0) {
-      close_transport_locked(exec_ctx, t, GRPC_ERROR_CREATE("goaway sent"));
+      close_transport_locked(
+          exec_ctx, t, GRPC_ERROR_CREATE_FROM_STATIC_STRING("goaway sent"));
     }
   }
 
@@ -898,22 +902,19 @@ void grpc_chttp2_add_incoming_goaway(grpc_exec_ctx *exec_ctx,
                                      grpc_chttp2_transport *t,
                                      uint32_t goaway_error,
                                      grpc_slice goaway_text) {
-  char *msg = grpc_dump_slice(goaway_text, GPR_DUMP_HEX | GPR_DUMP_ASCII);
-  GRPC_CHTTP2_IF_TRACING(
-      gpr_log(GPR_DEBUG, "got goaway [%d]: %s", goaway_error, msg));
-  grpc_slice_unref_internal(exec_ctx, goaway_text);
+  // GRPC_CHTTP2_IF_TRACING(
+  //     gpr_log(GPR_DEBUG, "got goaway [%d]: %s", goaway_error, msg));
   t->seen_goaway = 1;
   /* lie: use transient failure from the transport to indicate goaway has been
    * received */
   connectivity_state_set(
       exec_ctx, t, GRPC_CHANNEL_TRANSIENT_FAILURE,
       grpc_error_set_str(
-          grpc_error_set_int(GRPC_ERROR_CREATE("GOAWAY received"),
-                             GRPC_ERROR_INT_HTTP2_ERROR,
-                             (intptr_t)goaway_error),
-          GRPC_ERROR_STR_RAW_BYTES, msg),
+          grpc_error_set_int(
+              GRPC_ERROR_CREATE_FROM_STATIC_STRING("GOAWAY received"),
+              GRPC_ERROR_INT_HTTP2_ERROR, (intptr_t)goaway_error),
+          GRPC_ERROR_STR_RAW_BYTES, goaway_text),
       "got_goaway");
-  gpr_free(msg);
 }
 
 static void maybe_start_some_streams(grpc_exec_ctx *exec_ctx,
@@ -936,9 +937,10 @@ static void maybe_start_some_streams(grpc_exec_ctx *exec_ctx,
     t->next_stream_id += 2;
 
     if (t->next_stream_id >= MAX_CLIENT_STREAM_ID) {
-      connectivity_state_set(exec_ctx, t, GRPC_CHANNEL_TRANSIENT_FAILURE,
-                             GRPC_ERROR_CREATE("Stream IDs exhausted"),
-                             "no_more_stream_ids");
+      connectivity_state_set(
+          exec_ctx, t, GRPC_CHANNEL_TRANSIENT_FAILURE,
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Stream IDs exhausted"),
+          "no_more_stream_ids");
     }
 
     grpc_chttp2_stream_map_add(&t->stream_map, s->id, s);
@@ -952,9 +954,9 @@ static void maybe_start_some_streams(grpc_exec_ctx *exec_ctx,
          grpc_chttp2_list_pop_waiting_for_concurrency(t, &s)) {
     grpc_chttp2_cancel_stream(
         exec_ctx, t, s,
-        grpc_error_set_int(GRPC_ERROR_CREATE("Stream IDs exhausted"),
-                           GRPC_ERROR_INT_GRPC_STATUS,
-                           GRPC_STATUS_UNAVAILABLE));
+        grpc_error_set_int(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Stream IDs exhausted"),
+            GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAVAILABLE));
   }
 }
 
@@ -1003,11 +1005,11 @@ void grpc_chttp2_complete_closure_step(grpc_exec_ctx *exec_ctx,
   }
   if (error != GRPC_ERROR_NONE) {
     if (closure->error_data.error == GRPC_ERROR_NONE) {
-      closure->error_data.error =
-          GRPC_ERROR_CREATE("Error in HTTP transport completing operation");
-      closure->error_data.error =
-          grpc_error_set_str(closure->error_data.error,
-                             GRPC_ERROR_STR_TARGET_ADDRESS, t->peer_string);
+      closure->error_data.error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+          "Error in HTTP transport completing operation");
+      closure->error_data.error = grpc_error_set_str(
+          closure->error_data.error, GRPC_ERROR_STR_TARGET_ADDRESS,
+          grpc_slice_from_copied_string(t->peer_string));
     }
     closure->error_data.error =
         grpc_error_add_child(closure->error_data.error, error);
@@ -1182,10 +1184,11 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
           exec_ctx, t, s,
           grpc_error_set_int(
               grpc_error_set_int(
-                  grpc_error_set_int(
-                      GRPC_ERROR_CREATE("to-be-sent initial metadata size "
-                                        "exceeds peer limit"),
-                      GRPC_ERROR_INT_SIZE, (intptr_t)metadata_size),
+                  grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                         "to-be-sent initial metadata size "
+                                         "exceeds peer limit"),
+                                     GRPC_ERROR_INT_SIZE,
+                                     (intptr_t)metadata_size),
                   GRPC_ERROR_INT_LIMIT, (intptr_t)metadata_peer_limit),
               GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_RESOURCE_EXHAUSTED));
     } else {
@@ -1201,9 +1204,9 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
           } else {
             grpc_chttp2_cancel_stream(
                 exec_ctx, t, s,
-                grpc_error_set_int(GRPC_ERROR_CREATE("Transport closed"),
-                                   GRPC_ERROR_INT_GRPC_STATUS,
-                                   GRPC_STATUS_UNAVAILABLE));
+                grpc_error_set_int(
+                    GRPC_ERROR_CREATE_FROM_STATIC_STRING("Transport closed"),
+                    GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAVAILABLE));
           }
         } else {
           GPR_ASSERT(s->id != 0);
@@ -1220,7 +1223,7 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
         s->send_initial_metadata = NULL;
         grpc_chttp2_complete_closure_step(
             exec_ctx, t, s, &s->send_initial_metadata_finished,
-            GRPC_ERROR_CREATE_REFERENCING(
+            GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                 "Attempt to send initial metadata after stream was closed",
                 &s->write_closed_error, 1),
             "send_initial_metadata_finished");
@@ -1234,7 +1237,7 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
     if (s->write_closed) {
       grpc_chttp2_complete_closure_step(
           exec_ctx, t, s, &s->fetching_send_message_finished,
-          GRPC_ERROR_CREATE_REFERENCING(
+          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
               "Attempt to send message after stream was closed",
               &s->write_closed_error, 1),
           "fetching_send_message_finished");
@@ -1282,10 +1285,11 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
           exec_ctx, t, s,
           grpc_error_set_int(
               grpc_error_set_int(
-                  grpc_error_set_int(
-                      GRPC_ERROR_CREATE("to-be-sent trailing metadata size "
-                                        "exceeds peer limit"),
-                      GRPC_ERROR_INT_SIZE, (intptr_t)metadata_size),
+                  grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                         "to-be-sent trailing metadata size "
+                                         "exceeds peer limit"),
+                                     GRPC_ERROR_INT_SIZE,
+                                     (intptr_t)metadata_size),
                   GRPC_ERROR_INT_LIMIT, (intptr_t)metadata_peer_limit),
               GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_RESOURCE_EXHAUSTED));
     } else {
@@ -1298,8 +1302,9 @@ static void perform_stream_op_locked(grpc_exec_ctx *exec_ctx, void *stream_op,
             exec_ctx, t, s, &s->send_trailing_metadata_finished,
             grpc_metadata_batch_is_empty(op->send_trailing_metadata)
                 ? GRPC_ERROR_NONE
-                : GRPC_ERROR_CREATE("Attempt to send trailing metadata after "
-                                    "stream was closed"),
+                : GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                      "Attempt to send trailing metadata after "
+                      "stream was closed"),
             "send_trailing_metadata_finished");
       } else if (s->id != 0) {
         /* TODO(ctiller): check if there's flow control for any outstanding
@@ -1414,11 +1419,11 @@ static void send_goaway(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                         grpc_error *error) {
   t->sent_goaway_state = GRPC_CHTTP2_GOAWAY_SEND_SCHEDULED;
   grpc_http2_error_code http_error;
-  const char *msg;
-  grpc_error_get_status(error, gpr_inf_future(GPR_CLOCK_MONOTONIC), NULL, &msg,
-                        &http_error);
+  grpc_slice slice;
+  grpc_error_get_status(error, gpr_inf_future(GPR_CLOCK_MONOTONIC), NULL,
+                        &slice, &http_error);
   grpc_chttp2_goaway_append(t->last_new_stream_id, (uint32_t)http_error,
-                            grpc_slice_from_copied_string(msg), &t->qbuf);
+                            grpc_slice_ref_internal(slice), &t->qbuf);
   grpc_chttp2_initiate_write(exec_ctx, t, false, "goaway_sent");
   GRPC_ERROR_UNREF(error);
 }
@@ -1578,7 +1583,7 @@ static void remove_stream(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
     if (t->sent_goaway_state == GRPC_CHTTP2_GOAWAY_SENT) {
       close_transport_locked(
           exec_ctx, t,
-          GRPC_ERROR_CREATE_REFERENCING(
+          GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
               "Last stream closed after sending GOAWAY", &error, 1));
     }
   }
@@ -1619,8 +1624,8 @@ void grpc_chttp2_cancel_stream(grpc_exec_ctx *exec_ctx,
 void grpc_chttp2_fake_status(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                              grpc_chttp2_stream *s, grpc_error *error) {
   grpc_status_code status;
-  const char *msg;
-  grpc_error_get_status(error, s->deadline, &status, &msg, NULL);
+  grpc_slice slice;
+  grpc_error_get_status(error, s->deadline, &status, &slice, NULL);
 
   if (status != GRPC_STATUS_OK) {
     s->seen_error = true;
@@ -1641,13 +1646,13 @@ void grpc_chttp2_fake_status(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                           grpc_mdelem_from_slices(
                               exec_ctx, GRPC_MDSTR_GRPC_STATUS,
                               grpc_slice_from_copied_string(status_string))));
-    if (msg != NULL) {
+    if (!GRPC_SLICE_IS_EMPTY(slice)) {
       GRPC_LOG_IF_ERROR(
           "add_status_message",
           grpc_chttp2_incoming_metadata_buffer_replace_or_add(
               exec_ctx, &s->metadata_buffer[1],
               grpc_mdelem_from_slices(exec_ctx, GRPC_MDSTR_GRPC_MESSAGE,
-                                      grpc_slice_from_copied_string(msg))));
+                                      grpc_slice_ref_internal(slice))));
     }
     s->published_metadata[1] = GRPC_METADATA_SYNTHESIZED_FROM_FAKE;
     grpc_chttp2_maybe_complete_recv_trailing_metadata(exec_ctx, t, s);
@@ -1676,7 +1681,8 @@ static grpc_error *removal_error(grpc_error *extra_error, grpc_chttp2_stream *s,
   add_error(extra_error, refs, &nrefs);
   grpc_error *error = GRPC_ERROR_NONE;
   if (nrefs > 0) {
-    error = GRPC_ERROR_CREATE_REFERENCING(master_error_msg, refs, nrefs);
+    error = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(master_error_msg,
+                                                             refs, nrefs);
   }
   GRPC_ERROR_UNREF(extra_error);
   return error;
@@ -1770,12 +1776,13 @@ static void close_from_api(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
                            grpc_chttp2_stream *s, grpc_error *error) {
   grpc_slice hdr;
   grpc_slice status_hdr;
+  grpc_slice http_status_hdr;
   grpc_slice message_pfx;
   uint8_t *p;
   uint32_t len = 0;
   grpc_status_code grpc_status;
-  const char *msg;
-  grpc_error_get_status(error, s->deadline, &grpc_status, &msg, NULL);
+  grpc_slice slice;
+  grpc_error_get_status(error, s->deadline, &grpc_status, &slice, NULL);
 
   GPR_ASSERT(grpc_status >= 0 && (int)grpc_status < 100);
 
@@ -1785,6 +1792,26 @@ static void close_from_api(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
      It's complicated by the fact that our send machinery would be dead by
      the time we got around to sending this, so instead we ignore HPACK
      compression and just write the uncompressed bytes onto the wire. */
+  if (!s->sent_initial_metadata) {
+    http_status_hdr = grpc_slice_malloc(13);
+    p = GRPC_SLICE_START_PTR(http_status_hdr);
+    *p++ = 0x00;
+    *p++ = 7;
+    *p++ = ':';
+    *p++ = 's';
+    *p++ = 't';
+    *p++ = 'a';
+    *p++ = 't';
+    *p++ = 'u';
+    *p++ = 's';
+    *p++ = 3;
+    *p++ = '2';
+    *p++ = '0';
+    *p++ = '0';
+    GPR_ASSERT(p == GRPC_SLICE_END_PTR(http_status_hdr));
+    len += (uint32_t)GRPC_SLICE_LENGTH(http_status_hdr);
+  }
+
   status_hdr = grpc_slice_malloc(15 + (grpc_status >= 10));
   p = GRPC_SLICE_START_PTR(status_hdr);
   *p++ = 0x00; /* literal header, not indexed */
@@ -1811,32 +1838,30 @@ static void close_from_api(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   GPR_ASSERT(p == GRPC_SLICE_END_PTR(status_hdr));
   len += (uint32_t)GRPC_SLICE_LENGTH(status_hdr);
 
-  if (msg != NULL) {
-    size_t msg_len = strlen(msg);
-    GPR_ASSERT(msg_len <= UINT32_MAX);
-    uint32_t msg_len_len = GRPC_CHTTP2_VARINT_LENGTH((uint32_t)msg_len, 0);
-    message_pfx = grpc_slice_malloc(14 + msg_len_len);
-    p = GRPC_SLICE_START_PTR(message_pfx);
-    *p++ = 0x00; /* literal header, not indexed */
-    *p++ = 12;   /* len(grpc-message) */
-    *p++ = 'g';
-    *p++ = 'r';
-    *p++ = 'p';
-    *p++ = 'c';
-    *p++ = '-';
-    *p++ = 'm';
-    *p++ = 'e';
-    *p++ = 's';
-    *p++ = 's';
-    *p++ = 'a';
-    *p++ = 'g';
-    *p++ = 'e';
-    GRPC_CHTTP2_WRITE_VARINT((uint32_t)msg_len, 0, 0, p, (uint32_t)msg_len_len);
-    p += msg_len_len;
-    GPR_ASSERT(p == GRPC_SLICE_END_PTR(message_pfx));
-    len += (uint32_t)GRPC_SLICE_LENGTH(message_pfx);
-    len += (uint32_t)msg_len;
-  }
+  size_t msg_len = GRPC_SLICE_LENGTH(slice);
+  GPR_ASSERT(msg_len <= UINT32_MAX);
+  uint32_t msg_len_len = GRPC_CHTTP2_VARINT_LENGTH((uint32_t)msg_len, 0);
+  message_pfx = grpc_slice_malloc(14 + msg_len_len);
+  p = GRPC_SLICE_START_PTR(message_pfx);
+  *p++ = 0x00; /* literal header, not indexed */
+  *p++ = 12;   /* len(grpc-message) */
+  *p++ = 'g';
+  *p++ = 'r';
+  *p++ = 'p';
+  *p++ = 'c';
+  *p++ = '-';
+  *p++ = 'm';
+  *p++ = 'e';
+  *p++ = 's';
+  *p++ = 's';
+  *p++ = 'a';
+  *p++ = 'g';
+  *p++ = 'e';
+  GRPC_CHTTP2_WRITE_VARINT((uint32_t)msg_len, 0, 0, p, (uint32_t)msg_len_len);
+  p += msg_len_len;
+  GPR_ASSERT(p == GRPC_SLICE_END_PTR(message_pfx));
+  len += (uint32_t)GRPC_SLICE_LENGTH(message_pfx);
+  len += (uint32_t)msg_len;
 
   hdr = grpc_slice_malloc(9);
   p = GRPC_SLICE_START_PTR(hdr);
@@ -1852,11 +1877,12 @@ static void close_from_api(grpc_exec_ctx *exec_ctx, grpc_chttp2_transport *t,
   GPR_ASSERT(p == GRPC_SLICE_END_PTR(hdr));
 
   grpc_slice_buffer_add(&t->qbuf, hdr);
-  grpc_slice_buffer_add(&t->qbuf, status_hdr);
-  if (msg != NULL) {
-    grpc_slice_buffer_add(&t->qbuf, message_pfx);
-    grpc_slice_buffer_add(&t->qbuf, grpc_slice_from_copied_string(msg));
+  if (!s->sent_initial_metadata) {
+    grpc_slice_buffer_add(&t->qbuf, http_status_hdr);
   }
+  grpc_slice_buffer_add(&t->qbuf, status_hdr);
+  grpc_slice_buffer_add(&t->qbuf, message_pfx);
+  grpc_slice_buffer_add(&t->qbuf, grpc_slice_ref_internal(slice));
   grpc_slice_buffer_add(
       &t->qbuf, grpc_chttp2_rst_stream_create(s->id, GRPC_HTTP2_NO_ERROR,
                                               &s->stats.outgoing));
@@ -1931,9 +1957,9 @@ static grpc_error *try_http_parsing(grpc_exec_ctx *exec_ctx,
   if (parse_error == GRPC_ERROR_NONE &&
       (parse_error = grpc_http_parser_eof(&parser)) == GRPC_ERROR_NONE) {
     error = grpc_error_set_int(
-        grpc_error_set_int(
-            GRPC_ERROR_CREATE("Trying to connect an http1.x server"),
-            GRPC_ERROR_INT_HTTP_STATUS, response.status),
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                               "Trying to connect an http1.x server"),
+                           GRPC_ERROR_INT_HTTP_STATUS, response.status),
         GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAVAILABLE);
   }
   GRPC_ERROR_UNREF(parse_error);
@@ -1954,9 +1980,10 @@ static void read_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
 
   grpc_error *err = error;
   if (err != GRPC_ERROR_NONE) {
-    err = grpc_error_set_int(
-        GRPC_ERROR_CREATE_REFERENCING("Endpoint read failed", &err, 1),
-        GRPC_ERROR_INT_OCCURRED_DURING_WRITE, t->write_state);
+    err = grpc_error_set_int(GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                                 "Endpoint read failed", &err, 1),
+                             GRPC_ERROR_INT_OCCURRED_DURING_WRITE,
+                             t->write_state);
   }
   GPR_SWAP(grpc_error *, err, error);
   GRPC_ERROR_UNREF(err);
@@ -1977,8 +2004,8 @@ static void read_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
     if (errors[1] != GRPC_ERROR_NONE) {
       errors[2] = try_http_parsing(exec_ctx, t);
       GRPC_ERROR_UNREF(error);
-      error = GRPC_ERROR_CREATE_REFERENCING("Failed parsing HTTP/2", errors,
-                                            GPR_ARRAY_SIZE(errors));
+      error = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+          "Failed parsing HTTP/2", errors, GPR_ARRAY_SIZE(errors));
     }
     for (i = 0; i < GPR_ARRAY_SIZE(errors); i++) {
       GRPC_ERROR_UNREF(errors[i]);
@@ -2003,7 +2030,7 @@ static void read_action_locked(grpc_exec_ctx *exec_ctx, void *tp,
   GPR_TIMER_BEGIN("post_reading_action_locked", 0);
   bool keep_reading = false;
   if (error == GRPC_ERROR_NONE && t->closed) {
-    error = GRPC_ERROR_CREATE("Transport closed");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Transport closed");
   }
   if (error != GRPC_ERROR_NONE) {
     close_transport_locked(exec_ctx, t, GRPC_ERROR_REF(error));
@@ -2138,8 +2165,8 @@ static void keepalive_watchdog_fired_locked(grpc_exec_ctx *exec_ctx, void *arg,
   if (t->keepalive_state == GRPC_CHTTP2_KEEPALIVE_STATE_PINGING) {
     if (error == GRPC_ERROR_NONE) {
       t->keepalive_state = GRPC_CHTTP2_KEEPALIVE_STATE_DYING;
-      close_transport_locked(exec_ctx, t,
-                             GRPC_ERROR_CREATE("keepalive watchdog timeout"));
+      close_transport_locked(exec_ctx, t, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                              "keepalive watchdog timeout"));
     }
   } else {
     /** The watchdog timer should have been cancelled by
@@ -2338,7 +2365,8 @@ void grpc_chttp2_incoming_byte_stream_push(grpc_exec_ctx *exec_ctx,
   gpr_mu_lock(&bs->slice_mu);
   if (bs->remaining_bytes < GRPC_SLICE_LENGTH(slice)) {
     incoming_byte_stream_publish_error(
-        exec_ctx, bs, GRPC_ERROR_CREATE("Too many bytes in stream"));
+        exec_ctx, bs,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Too many bytes in stream"));
   } else {
     bs->remaining_bytes -= (uint32_t)GRPC_SLICE_LENGTH(slice);
     if (bs->on_next != NULL) {
@@ -2358,7 +2386,7 @@ void grpc_chttp2_incoming_byte_stream_finished(
   if (error == GRPC_ERROR_NONE) {
     gpr_mu_lock(&bs->slice_mu);
     if (bs->remaining_bytes != 0) {
-      error = GRPC_ERROR_CREATE("Truncated message");
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Truncated message");
     }
     gpr_mu_unlock(&bs->slice_mu);
   }
@@ -2438,9 +2466,9 @@ static void benign_reclaimer_locked(grpc_exec_ctx *exec_ctx, void *arg,
               t->peer_string);
     }
     send_goaway(exec_ctx, t,
-                grpc_error_set_int(GRPC_ERROR_CREATE("Buffers full"),
-                                   GRPC_ERROR_INT_HTTP2_ERROR,
-                                   GRPC_HTTP2_ENHANCE_YOUR_CALM));
+                grpc_error_set_int(
+                    GRPC_ERROR_CREATE_FROM_STATIC_STRING("Buffers full"),
+                    GRPC_ERROR_INT_HTTP2_ERROR, GRPC_HTTP2_ENHANCE_YOUR_CALM));
   } else if (error == GRPC_ERROR_NONE && grpc_resource_quota_trace) {
     gpr_log(GPR_DEBUG,
             "HTTP2: %s - skip benign reclamation, there are still %" PRIdPTR
@@ -2467,9 +2495,10 @@ static void destructive_reclaimer_locked(grpc_exec_ctx *exec_ctx, void *arg,
               s->id);
     }
     grpc_chttp2_cancel_stream(
-        exec_ctx, t, s, grpc_error_set_int(GRPC_ERROR_CREATE("Buffers full"),
-                                           GRPC_ERROR_INT_HTTP2_ERROR,
-                                           GRPC_HTTP2_ENHANCE_YOUR_CALM));
+        exec_ctx, t, s,
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING("Buffers full"),
+                           GRPC_ERROR_INT_HTTP2_ERROR,
+                           GRPC_HTTP2_ENHANCE_YOUR_CALM));
     if (n > 1) {
       /* Since we cancel one stream per destructive reclamation, if
          there are more streams left, we can immediately post a new
diff --git a/src/core/ext/transport/chttp2/transport/frame_data.c b/src/core/ext/transport/chttp2/transport/frame_data.c
index f9b9e1b309..6e9258ee7e 100644
--- a/src/core/ext/transport/chttp2/transport/frame_data.c
+++ b/src/core/ext/transport/chttp2/transport/frame_data.c
@@ -54,7 +54,8 @@ void grpc_chttp2_data_parser_destroy(grpc_exec_ctx *exec_ctx,
                                      grpc_chttp2_data_parser *parser) {
   if (parser->parsing_frame != NULL) {
     grpc_chttp2_incoming_byte_stream_finished(
-        exec_ctx, parser->parsing_frame, GRPC_ERROR_CREATE("Parser destroyed"));
+        exec_ctx, parser->parsing_frame,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Parser destroyed"));
   }
   GRPC_ERROR_UNREF(parser->error);
 }
@@ -65,8 +66,9 @@ grpc_error *grpc_chttp2_data_parser_begin_frame(grpc_chttp2_data_parser *parser,
   if (flags & ~GRPC_CHTTP2_DATA_FLAG_END_STREAM) {
     char *msg;
     gpr_asprintf(&msg, "unsupported data flags: 0x%02x", flags);
-    grpc_error *err = grpc_error_set_int(
-        GRPC_ERROR_CREATE(msg), GRPC_ERROR_INT_STREAM_ID, (intptr_t)stream_id);
+    grpc_error *err =
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg),
+                           GRPC_ERROR_INT_STREAM_ID, (intptr_t)stream_id);
     gpr_free(msg);
     return err;
   }
@@ -173,13 +175,13 @@ static grpc_error *parse_inner(grpc_exec_ctx *exec_ctx,
           break;
         default:
           gpr_asprintf(&msg, "Bad GRPC frame type 0x%02x", p->frame_type);
-          p->error = GRPC_ERROR_CREATE(msg);
+          p->error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
           p->error = grpc_error_set_int(p->error, GRPC_ERROR_INT_STREAM_ID,
                                         (intptr_t)s->id);
           gpr_free(msg);
           msg = grpc_dump_slice(slice, GPR_DUMP_HEX | GPR_DUMP_ASCII);
-          p->error =
-              grpc_error_set_str(p->error, GRPC_ERROR_STR_RAW_BYTES, msg);
+          p->error = grpc_error_set_str(p->error, GRPC_ERROR_STR_RAW_BYTES,
+                                        grpc_slice_from_copied_string(msg));
           gpr_free(msg);
           p->error =
               grpc_error_set_int(p->error, GRPC_ERROR_INT_OFFSET, cur - beg);
@@ -265,7 +267,8 @@ static grpc_error *parse_inner(grpc_exec_ctx *exec_ctx,
       }
   }
 
-  GPR_UNREACHABLE_CODE(return GRPC_ERROR_CREATE("Should never reach here"));
+  GPR_UNREACHABLE_CODE(
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Should never reach here"));
 }
 
 grpc_error *grpc_chttp2_data_parser_parse(grpc_exec_ctx *exec_ctx, void *parser,
diff --git a/src/core/ext/transport/chttp2/transport/frame_goaway.c b/src/core/ext/transport/chttp2/transport/frame_goaway.c
index d99d486c1b..001271dd22 100644
--- a/src/core/ext/transport/chttp2/transport/frame_goaway.c
+++ b/src/core/ext/transport/chttp2/transport/frame_goaway.c
@@ -54,7 +54,7 @@ grpc_error *grpc_chttp2_goaway_parser_begin_frame(grpc_chttp2_goaway_parser *p,
   if (length < 8) {
     char *msg;
     gpr_asprintf(&msg, "goaway frame too short (%d bytes)", length);
-    grpc_error *err = GRPC_ERROR_CREATE(msg);
+    grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return err;
   }
@@ -156,7 +156,8 @@ grpc_error *grpc_chttp2_goaway_parser_parse(grpc_exec_ctx *exec_ctx,
       }
       return GRPC_ERROR_NONE;
   }
-  GPR_UNREACHABLE_CODE(return GRPC_ERROR_CREATE("Should never reach here"));
+  GPR_UNREACHABLE_CODE(
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Should never reach here"));
 }
 
 void grpc_chttp2_goaway_append(uint32_t last_stream_id, uint32_t error_code,
diff --git a/src/core/ext/transport/chttp2/transport/frame_ping.c b/src/core/ext/transport/chttp2/transport/frame_ping.c
index 9b4b1a7b84..de8462a17e 100644
--- a/src/core/ext/transport/chttp2/transport/frame_ping.c
+++ b/src/core/ext/transport/chttp2/transport/frame_ping.c
@@ -71,7 +71,7 @@ grpc_error *grpc_chttp2_ping_parser_begin_frame(grpc_chttp2_ping_parser *parser,
   if (flags & 0xfe || length != 8) {
     char *msg;
     gpr_asprintf(&msg, "invalid ping: length=%d, flags=%02x", length, flags);
-    grpc_error *error = GRPC_ERROR_CREATE(msg);
+    grpc_error *error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return error;
   }
diff --git a/src/core/ext/transport/chttp2/transport/frame_rst_stream.c b/src/core/ext/transport/chttp2/transport/frame_rst_stream.c
index cb017e75f0..225f15c77c 100644
--- a/src/core/ext/transport/chttp2/transport/frame_rst_stream.c
+++ b/src/core/ext/transport/chttp2/transport/frame_rst_stream.c
@@ -76,7 +76,7 @@ grpc_error *grpc_chttp2_rst_stream_parser_begin_frame(
     char *msg;
     gpr_asprintf(&msg, "invalid rst_stream: length=%d, flags=%02x", length,
                  flags);
-    grpc_error *err = GRPC_ERROR_CREATE(msg);
+    grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return err;
   }
@@ -112,8 +112,9 @@ grpc_error *grpc_chttp2_rst_stream_parser_parse(grpc_exec_ctx *exec_ctx,
       char *message;
       gpr_asprintf(&message, "Received RST_STREAM with error code %d", reason);
       error = grpc_error_set_int(
-          grpc_error_set_str(GRPC_ERROR_CREATE("RST_STREAM"),
-                             GRPC_ERROR_STR_GRPC_MESSAGE, message),
+          grpc_error_set_str(GRPC_ERROR_CREATE_FROM_STATIC_STRING("RST_STREAM"),
+                             GRPC_ERROR_STR_GRPC_MESSAGE,
+                             grpc_slice_from_copied_string(message)),
           GRPC_ERROR_INT_HTTP2_ERROR, (intptr_t)reason);
       gpr_free(message);
     }
diff --git a/src/core/ext/transport/chttp2/transport/frame_settings.c b/src/core/ext/transport/chttp2/transport/frame_settings.c
index 82290e34cd..16881c0707 100644
--- a/src/core/ext/transport/chttp2/transport/frame_settings.c
+++ b/src/core/ext/transport/chttp2/transport/frame_settings.c
@@ -131,13 +131,16 @@ grpc_error *grpc_chttp2_settings_parser_begin_frame(
   if (flags == GRPC_CHTTP2_FLAG_ACK) {
     parser->is_ack = 1;
     if (length != 0) {
-      return GRPC_ERROR_CREATE("non-empty settings ack frame received");
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+          "non-empty settings ack frame received");
     }
     return GRPC_ERROR_NONE;
   } else if (flags != 0) {
-    return GRPC_ERROR_CREATE("invalid flags on settings frame");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "invalid flags on settings frame");
   } else if (length % 6 != 0) {
-    return GRPC_ERROR_CREATE("settings frames must be a multiple of six bytes");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "settings frames must be a multiple of six bytes");
   } else {
     return GRPC_ERROR_NONE;
   }
@@ -229,7 +232,7 @@ grpc_error *grpc_chttp2_settings_parser_parse(grpc_exec_ctx *exec_ctx, void *p,
                     &t->qbuf);
                 gpr_asprintf(&msg, "invalid value %u passed for %s",
                              parser->value, sp->name);
-                grpc_error *err = GRPC_ERROR_CREATE(msg);
+                grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
                 gpr_free(msg);
                 return err;
             }
diff --git a/src/core/ext/transport/chttp2/transport/frame_window_update.c b/src/core/ext/transport/chttp2/transport/frame_window_update.c
index 8fa0bb471a..b76b6f6f47 100644
--- a/src/core/ext/transport/chttp2/transport/frame_window_update.c
+++ b/src/core/ext/transport/chttp2/transport/frame_window_update.c
@@ -70,7 +70,7 @@ grpc_error *grpc_chttp2_window_update_parser_begin_frame(
     char *msg;
     gpr_asprintf(&msg, "invalid window update: length=%d, flags=%02x", length,
                  flags);
-    grpc_error *err = GRPC_ERROR_CREATE(msg);
+    grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return err;
   }
@@ -102,7 +102,7 @@ grpc_error *grpc_chttp2_window_update_parser_parse(
     if (received_update == 0 || (received_update & 0x80000000u)) {
       char *msg;
       gpr_asprintf(&msg, "invalid window update bytes: %d", p->amount);
-      grpc_error *err = GRPC_ERROR_CREATE(msg);
+      grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
       gpr_free(msg);
       return err;
     }
diff --git a/src/core/ext/transport/chttp2/transport/hpack_parser.c b/src/core/ext/transport/chttp2/transport/hpack_parser.c
index 40f5120308..5099d736bf 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_parser.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_parser.c
@@ -693,7 +693,7 @@ static grpc_error *on_hdr(grpc_exec_ctx *exec_ctx, grpc_chttp2_hpack_parser *p,
   }
   if (p->on_header == NULL) {
     GRPC_MDELEM_UNREF(exec_ctx, md);
-    return GRPC_ERROR_CREATE("on_header callback not set");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("on_header callback not set");
   }
   p->on_header(exec_ctx, p->on_header_user_data, md);
   return GRPC_ERROR_NONE;
@@ -810,7 +810,8 @@ static grpc_error *finish_indexed_field(grpc_exec_ctx *exec_ctx,
   grpc_mdelem md = grpc_chttp2_hptbl_lookup(&p->table, p->index);
   if (GRPC_MDISNULL(md)) {
     return grpc_error_set_int(
-        grpc_error_set_int(GRPC_ERROR_CREATE("Invalid HPACK index received"),
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                               "Invalid HPACK index received"),
                            GRPC_ERROR_INT_INDEX, (intptr_t)p->index),
         GRPC_ERROR_INT_SIZE, (intptr_t)p->table.num_ents);
   }
@@ -1074,7 +1075,7 @@ static grpc_error *parse_max_tbl_size(grpc_exec_ctx *exec_ctx,
   if (p->dynamic_table_update_allowed == 0) {
     return parse_error(
         exec_ctx, p, cur, end,
-        GRPC_ERROR_CREATE(
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING(
             "More than two max table size changes in a single frame"));
   }
   p->dynamic_table_update_allowed--;
@@ -1092,7 +1093,7 @@ static grpc_error *parse_max_tbl_size_x(grpc_exec_ctx *exec_ctx,
   if (p->dynamic_table_update_allowed == 0) {
     return parse_error(
         exec_ctx, p, cur, end,
-        GRPC_ERROR_CREATE(
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING(
             "More than two max table size changes in a single frame"));
   }
   p->dynamic_table_update_allowed--;
@@ -1126,7 +1127,7 @@ static grpc_error *parse_illegal_op(grpc_exec_ctx *exec_ctx,
   GPR_ASSERT(cur != end);
   char *msg;
   gpr_asprintf(&msg, "Illegal hpack op code %d", *cur);
-  grpc_error *err = GRPC_ERROR_CREATE(msg);
+  grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
   gpr_free(msg);
   return parse_error(exec_ctx, p, cur, end, err);
 }
@@ -1246,7 +1247,7 @@ error:
                "integer overflow in hpack integer decoding: have 0x%08x, "
                "got byte 0x%02x on byte 5",
                *p->parsing.value, *cur);
-  grpc_error *err = GRPC_ERROR_CREATE(msg);
+  grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
   gpr_free(msg);
   return parse_error(exec_ctx, p, cur, end, err);
 }
@@ -1275,7 +1276,7 @@ static grpc_error *parse_value5up(grpc_exec_ctx *exec_ctx,
                "integer overflow in hpack integer decoding: have 0x%08x, "
                "got byte 0x%02x sometime after byte 5",
                *p->parsing.value, *cur);
-  grpc_error *err = GRPC_ERROR_CREATE(msg);
+  grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
   gpr_free(msg);
   return parse_error(exec_ctx, p, cur, end, err);
 }
@@ -1333,8 +1334,9 @@ static grpc_error *append_string(grpc_exec_ctx *exec_ctx,
       bits = inverse_base64[*cur];
       ++cur;
       if (bits == 255)
-        return parse_error(exec_ctx, p, cur, end,
-                           GRPC_ERROR_CREATE("Illegal base64 character"));
+        return parse_error(
+            exec_ctx, p, cur, end,
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Illegal base64 character"));
       else if (bits == 64)
         goto b64_byte0;
       p->base64_buffer = bits << 18;
@@ -1348,8 +1350,9 @@ static grpc_error *append_string(grpc_exec_ctx *exec_ctx,
       bits = inverse_base64[*cur];
       ++cur;
       if (bits == 255)
-        return parse_error(exec_ctx, p, cur, end,
-                           GRPC_ERROR_CREATE("Illegal base64 character"));
+        return parse_error(
+            exec_ctx, p, cur, end,
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Illegal base64 character"));
       else if (bits == 64)
         goto b64_byte1;
       p->base64_buffer |= bits << 12;
@@ -1363,8 +1366,9 @@ static grpc_error *append_string(grpc_exec_ctx *exec_ctx,
       bits = inverse_base64[*cur];
       ++cur;
       if (bits == 255)
-        return parse_error(exec_ctx, p, cur, end,
-                           GRPC_ERROR_CREATE("Illegal base64 character"));
+        return parse_error(
+            exec_ctx, p, cur, end,
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Illegal base64 character"));
       else if (bits == 64)
         goto b64_byte2;
       p->base64_buffer |= bits << 6;
@@ -1378,8 +1382,9 @@ static grpc_error *append_string(grpc_exec_ctx *exec_ctx,
       bits = inverse_base64[*cur];
       ++cur;
       if (bits == 255)
-        return parse_error(exec_ctx, p, cur, end,
-                           GRPC_ERROR_CREATE("Illegal base64 character"));
+        return parse_error(
+            exec_ctx, p, cur, end,
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Illegal base64 character"));
       else if (bits == 64)
         goto b64_byte3;
       p->base64_buffer |= bits;
@@ -1391,7 +1396,8 @@ static grpc_error *append_string(grpc_exec_ctx *exec_ctx,
       goto b64_byte0;
   }
   GPR_UNREACHABLE_CODE(return parse_error(
-      exec_ctx, p, cur, end, GRPC_ERROR_CREATE("Should never reach here")));
+      exec_ctx, p, cur, end,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Should never reach here")));
 }
 
 static grpc_error *finish_str(grpc_exec_ctx *exec_ctx,
@@ -1406,16 +1412,16 @@ static grpc_error *finish_str(grpc_exec_ctx *exec_ctx,
     case B64_BYTE0:
       break;
     case B64_BYTE1:
-      return parse_error(
-          exec_ctx, p, cur, end,
-          GRPC_ERROR_CREATE("illegal base64 encoding")); /* illegal encoding */
+      return parse_error(exec_ctx, p, cur, end,
+                         GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                             "illegal base64 encoding")); /* illegal encoding */
     case B64_BYTE2:
       bits = p->base64_buffer;
       if (bits & 0xffff) {
         char *msg;
         gpr_asprintf(&msg, "trailing bits in base64 encoding: 0x%04x",
                      bits & 0xffff);
-        grpc_error *err = GRPC_ERROR_CREATE(msg);
+        grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
         gpr_free(msg);
         return parse_error(exec_ctx, p, cur, end, err);
       }
@@ -1428,7 +1434,7 @@ static grpc_error *finish_str(grpc_exec_ctx *exec_ctx,
         char *msg;
         gpr_asprintf(&msg, "trailing bits in base64 encoding: 0x%02x",
                      bits & 0xff);
-        grpc_error *err = GRPC_ERROR_CREATE(msg);
+        grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
         gpr_free(msg);
         return parse_error(exec_ctx, p, cur, end, err);
       }
@@ -1550,7 +1556,8 @@ static grpc_error *is_binary_indexed_header(grpc_chttp2_hpack_parser *p,
   grpc_mdelem elem = grpc_chttp2_hptbl_lookup(&p->table, p->index);
   if (GRPC_MDISNULL(elem)) {
     return grpc_error_set_int(
-        grpc_error_set_int(GRPC_ERROR_CREATE("Invalid HPACK index received"),
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                               "Invalid HPACK index received"),
                            GRPC_ERROR_INT_INDEX, (intptr_t)p->index),
         GRPC_ERROR_INT_SIZE, (intptr_t)p->table.num_ents);
   }
@@ -1620,13 +1627,18 @@ void grpc_chttp2_hpack_parser_destroy(grpc_exec_ctx *exec_ctx,
 grpc_error *grpc_chttp2_hpack_parser_parse(grpc_exec_ctx *exec_ctx,
                                            grpc_chttp2_hpack_parser *p,
                                            grpc_slice slice) {
-  /* TODO(ctiller): limit the distance of end from beg, and perform multiple
-     steps in the event of a large chunk of data to limit
-     stack space usage when no tail call optimization is
-     available */
+/* max number of bytes to parse at a time... limits call stack depth on
+ * compilers without TCO */
+#define MAX_PARSE_LENGTH 1024
   p->current_slice_refcount = slice.refcount;
-  grpc_error *error = p->state(exec_ctx, p, GRPC_SLICE_START_PTR(slice),
-                               GRPC_SLICE_END_PTR(slice));
+  uint8_t *start = GRPC_SLICE_START_PTR(slice);
+  uint8_t *end = GRPC_SLICE_END_PTR(slice);
+  grpc_error *error = GRPC_ERROR_NONE;
+  while (start != end && error == GRPC_ERROR_NONE) {
+    uint8_t *target = start + GPR_MIN(MAX_PARSE_LENGTH, end - start);
+    error = p->state(exec_ctx, p, start, target);
+    start = target;
+  }
   p->current_slice_refcount = NULL;
   return error;
 }
@@ -1670,7 +1682,7 @@ grpc_error *grpc_chttp2_header_parser_parse(grpc_exec_ctx *exec_ctx,
   if (is_last) {
     if (parser->is_boundary && parser->state != parse_begin) {
       GPR_TIMER_END("grpc_chttp2_hpack_parser_parse", 0);
-      return GRPC_ERROR_CREATE(
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
           "end of header frame not aligned with a hpack record boundary");
     }
     /* need to check for null stream: this can occur if we receive an invalid
@@ -1678,7 +1690,8 @@ grpc_error *grpc_chttp2_header_parser_parse(grpc_exec_ctx *exec_ctx,
     if (s != NULL) {
       if (parser->is_boundary) {
         if (s->header_frames_received == GPR_ARRAY_SIZE(s->metadata_buffer)) {
-          return GRPC_ERROR_CREATE("Too many trailer frames");
+          return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+              "Too many trailer frames");
         }
         s->published_metadata[s->header_frames_received] =
             GRPC_METADATA_PUBLISHED_FROM_WIRE;
diff --git a/src/core/ext/transport/chttp2/transport/hpack_table.c b/src/core/ext/transport/chttp2/transport/hpack_table.c
index 62dd1b8cab..9dd41fdbe1 100644
--- a/src/core/ext/transport/chttp2/transport/hpack_table.c
+++ b/src/core/ext/transport/chttp2/transport/hpack_table.c
@@ -280,7 +280,7 @@ grpc_error *grpc_chttp2_hptbl_set_current_table_size(grpc_exec_ctx *exec_ctx,
     gpr_asprintf(&msg,
                  "Attempt to make hpack table %d bytes when max is %d bytes",
                  bytes, tbl->max_bytes);
-    grpc_error *err = GRPC_ERROR_CREATE(msg);
+    grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return err;
   }
@@ -317,7 +317,7 @@ grpc_error *grpc_chttp2_hptbl_add(grpc_exec_ctx *exec_ctx,
         "HPACK max table size reduced to %d but not reflected by hpack "
         "stream (still at %d)",
         tbl->max_bytes, tbl->current_table_bytes);
-    grpc_error *err = GRPC_ERROR_CREATE(msg);
+    grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return err;
   }
diff --git a/src/core/ext/transport/chttp2/transport/parsing.c b/src/core/ext/transport/chttp2/transport/parsing.c
index 7efc8c63c9..7e457ced27 100644
--- a/src/core/ext/transport/chttp2/transport/parsing.c
+++ b/src/core/ext/transport/chttp2/transport/parsing.c
@@ -116,7 +116,7 @@ grpc_error *grpc_chttp2_perform_read(grpc_exec_ctx *exec_ctx,
               GRPC_CHTTP2_CLIENT_CONNECT_STRING[t->deframe_state],
               (int)(uint8_t)GRPC_CHTTP2_CLIENT_CONNECT_STRING[t->deframe_state],
               *cur, (int)*cur, t->deframe_state);
-          err = GRPC_ERROR_CREATE(msg);
+          err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
           gpr_free(msg);
           return err;
         }
@@ -219,7 +219,7 @@ grpc_error *grpc_chttp2_perform_read(grpc_exec_ctx *exec_ctx,
                      t->incoming_frame_size,
                      t->settings[GRPC_ACKED_SETTINGS]
                                 [GRPC_CHTTP2_SETTINGS_MAX_FRAME_SIZE]);
-        err = GRPC_ERROR_CREATE(msg);
+        err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
         gpr_free(msg);
         return err;
       }
@@ -278,7 +278,7 @@ static grpc_error *init_frame_parser(grpc_exec_ctx *exec_ctx,
     gpr_asprintf(
         &msg, "Expected SETTINGS frame as the first frame, got frame type %d",
         t->incoming_frame_type);
-    grpc_error *err = GRPC_ERROR_CREATE(msg);
+    grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return err;
   }
@@ -288,7 +288,7 @@ static grpc_error *init_frame_parser(grpc_exec_ctx *exec_ctx,
       char *msg;
       gpr_asprintf(&msg, "Expected CONTINUATION frame, got frame type %02x",
                    t->incoming_frame_type);
-      grpc_error *err = GRPC_ERROR_CREATE(msg);
+      grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
       gpr_free(msg);
       return err;
     }
@@ -299,7 +299,7 @@ static grpc_error *init_frame_parser(grpc_exec_ctx *exec_ctx,
           "Expected CONTINUATION frame for grpc_chttp2_stream %08x, got "
           "grpc_chttp2_stream %08x",
           t->expect_continuation_stream_id, t->incoming_stream_id);
-      grpc_error *err = GRPC_ERROR_CREATE(msg);
+      grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
       gpr_free(msg);
       return err;
     }
@@ -311,7 +311,8 @@ static grpc_error *init_frame_parser(grpc_exec_ctx *exec_ctx,
     case GRPC_CHTTP2_FRAME_HEADER:
       return init_header_frame_parser(exec_ctx, t, 0);
     case GRPC_CHTTP2_FRAME_CONTINUATION:
-      return GRPC_ERROR_CREATE("Unexpected CONTINUATION frame");
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+          "Unexpected CONTINUATION frame");
     case GRPC_CHTTP2_FRAME_RST_STREAM:
       return init_rst_stream_parser(exec_ctx, t);
     case GRPC_CHTTP2_FRAME_SETTINGS:
@@ -371,7 +372,7 @@ static grpc_error *update_incoming_window(grpc_exec_ctx *exec_ctx,
     char *msg;
     gpr_asprintf(&msg, "frame of size %d overflows incoming window of %" PRId64,
                  t->incoming_frame_size, t->incoming_window);
-    grpc_error *err = GRPC_ERROR_CREATE(msg);
+    grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return err;
   }
@@ -409,7 +410,7 @@ static grpc_error *update_incoming_window(grpc_exec_ctx *exec_ctx,
                      s->incoming_window_delta +
                          t->settings[GRPC_ACKED_SETTINGS]
                                     [GRPC_CHTTP2_SETTINGS_INITIAL_WINDOW_SIZE]);
-        grpc_error *err = GRPC_ERROR_CREATE(msg);
+        grpc_error *err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
         gpr_free(msg);
         return err;
       }
@@ -542,7 +543,8 @@ static void on_initial_header(grpc_exec_ctx *exec_ctx, void *tp,
       grpc_chttp2_cancel_stream(
           exec_ctx, t, s,
           grpc_error_set_int(
-              GRPC_ERROR_CREATE("received initial metadata size exceeds limit"),
+              GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                  "received initial metadata size exceeds limit"),
               GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_RESOURCE_EXHAUSTED));
       grpc_chttp2_parsing_become_skip_parser(exec_ctx, t);
       s->seen_error = true;
@@ -598,9 +600,10 @@ static void on_trailing_header(grpc_exec_ctx *exec_ctx, void *tp,
             new_size, metadata_size_limit);
     grpc_chttp2_cancel_stream(
         exec_ctx, t, s,
-        grpc_error_set_int(
-            GRPC_ERROR_CREATE("received trailing metadata size exceeds limit"),
-            GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_RESOURCE_EXHAUSTED));
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                               "received trailing metadata size exceeds limit"),
+                           GRPC_ERROR_INT_GRPC_STATUS,
+                           GRPC_STATUS_RESOURCE_EXHAUSTED));
     grpc_chttp2_parsing_become_skip_parser(exec_ctx, t);
     s->seen_error = true;
     GRPC_MDELEM_UNREF(exec_ctx, md);
@@ -771,7 +774,8 @@ static grpc_error *init_goaway_parser(grpc_exec_ctx *exec_ctx,
 static grpc_error *init_settings_frame_parser(grpc_exec_ctx *exec_ctx,
                                               grpc_chttp2_transport *t) {
   if (t->incoming_stream_id != 0) {
-    return GRPC_ERROR_CREATE("Settings frame received for grpc_chttp2_stream");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Settings frame received for grpc_chttp2_stream");
   }
 
   grpc_error *err = grpc_chttp2_settings_parser_begin_frame(
diff --git a/src/core/ext/transport/cronet/transport/cronet_transport.c b/src/core/ext/transport/cronet/transport/cronet_transport.c
index 450d9ab23a..952690eba7 100644
--- a/src/core/ext/transport/cronet/transport/cronet_transport.c
+++ b/src/core/ext/transport/cronet/transport/cronet_transport.c
@@ -128,6 +128,7 @@ struct read_state {
   int received_bytes;
   int remaining_bytes;
   int length_field;
+  bool compressed;
   char grpc_header_bytes[GRPC_HEADER_SIZE_IN_BYTES];
   char *payload_field;
   bool read_stream_closed;
@@ -289,7 +290,7 @@ static void maybe_flush_read(stream_obj *s) {
 }
 
 static grpc_error *make_error_with_desc(int error_code, const char *desc) {
-  grpc_error *error = GRPC_ERROR_CREATE(desc);
+  grpc_error *error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc);
   error = grpc_error_set_int(error, GRPC_ERROR_INT_GRPC_STATUS, error_code);
   return error;
 }
@@ -484,6 +485,16 @@ static void on_response_headers_received(
   CRONET_LOG(GPR_DEBUG, "R: on_response_headers_received(%p, %p, %s)", stream,
              headers, negotiated_protocol);
   stream_obj *s = (stream_obj *)stream->annotation;
+
+  /* Identify if this is a header or a trailer (in a trailer-only response case)
+   */
+  for (size_t i = 0; i < headers->count; i++) {
+    if (0 == strcmp("grpc-status", headers->headers[i].key)) {
+      on_response_trailers_received(stream, headers);
+      return;
+    }
+  }
+
   gpr_mu_lock(&s->mu);
   memset(&s->state.rs.initial_metadata, 0,
          sizeof(s->state.rs.initial_metadata));
@@ -507,6 +518,7 @@ static void on_response_headers_received(
      is closed */
     GPR_ASSERT(s->state.rs.length_field_received == false);
     s->state.rs.read_buffer = s->state.rs.grpc_header_bytes;
+    s->state.rs.compressed = false;
     s->state.rs.received_bytes = 0;
     s->state.rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
     CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
@@ -641,7 +653,7 @@ static void on_response_trailers_received(
 */
 static void create_grpc_frame(grpc_slice_buffer *write_slice_buffer,
                               char **pp_write_buffer,
-                              size_t *p_write_buffer_size) {
+                              size_t *p_write_buffer_size, uint32_t flags) {
   grpc_slice slice = grpc_slice_buffer_take_first(write_slice_buffer);
   size_t length = GRPC_SLICE_LENGTH(slice);
   *p_write_buffer_size = length + GRPC_HEADER_SIZE_IN_BYTES;
@@ -650,7 +662,9 @@ static void create_grpc_frame(grpc_slice_buffer *write_slice_buffer,
   *pp_write_buffer = write_buffer;
   uint8_t *p = (uint8_t *)write_buffer;
   /* Append 5 byte header */
-  *p++ = 0;
+  /* Compressed flag */
+  *p++ = (flags & GRPC_WRITE_INTERNAL_COMPRESS) ? 1 : 0;
+  /* Message length */
   *p++ = (uint8_t)(length >> 24);
   *p++ = (uint8_t)(length >> 16);
   *p++ = (uint8_t)(length >> 8);
@@ -728,14 +742,16 @@ static void convert_metadata_to_cronet_headers(
   *p_num_headers = (size_t)num_headers;
 }
 
-static int parse_grpc_header(const uint8_t *data) {
+static void parse_grpc_header(const uint8_t *data, int *length,
+                              bool *compressed) {
+  const uint8_t c = *data;
   const uint8_t *p = data + 1;
-  int length = 0;
-  length |= ((uint8_t)*p++) << 24;
-  length |= ((uint8_t)*p++) << 16;
-  length |= ((uint8_t)*p++) << 8;
-  length |= ((uint8_t)*p++);
-  return length;
+  *compressed = ((c & 0x01) == 0x01);
+  *length = 0;
+  *length |= ((uint8_t)*p++) << 24;
+  *length |= ((uint8_t)*p++) << 16;
+  *length |= ((uint8_t)*p++) << 8;
+  *length |= ((uint8_t)*p++);
 }
 
 static bool header_has_authority(grpc_linked_mdelem *head) {
@@ -788,7 +804,8 @@ static bool op_can_be_run(grpc_transport_stream_op *curr_op,
     else if (!stream_state->state_callback_received[OP_SEND_INITIAL_METADATA])
       result = false;
     /* we haven't received headers yet. */
-    else if (!stream_state->state_callback_received[OP_RECV_INITIAL_METADATA])
+    else if (!stream_state->state_callback_received[OP_RECV_INITIAL_METADATA] &&
+             !stream_state->state_op_done[OP_RECV_TRAILING_METADATA])
       result = false;
   } else if (op_id == OP_SEND_MESSAGE) {
     /* already executed (note we're checking op specific state, not stream
@@ -801,7 +818,8 @@ static bool op_can_be_run(grpc_transport_stream_op *curr_op,
     /* already executed */
     if (op_state->state_op_done[OP_RECV_MESSAGE]) result = false;
     /* we haven't received headers yet. */
-    else if (!stream_state->state_callback_received[OP_RECV_INITIAL_METADATA])
+    else if (!stream_state->state_callback_received[OP_RECV_INITIAL_METADATA] &&
+             !stream_state->state_op_done[OP_RECV_TRAILING_METADATA])
       result = false;
   } else if (op_id == OP_RECV_TRAILING_METADATA) {
     /* already executed */
@@ -955,12 +973,6 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       grpc_slice_buffer_init(&write_slice_buffer);
       grpc_byte_stream_next(NULL, stream_op->send_message, &slice,
                             stream_op->send_message->length, NULL);
-      /* Check that compression flag is OFF. We don't support compression yet.
-       */
-      if (stream_op->send_message->flags != 0) {
-        gpr_log(GPR_ERROR, "Compression is not supported");
-        GPR_ASSERT(stream_op->send_message->flags == 0);
-      }
       grpc_slice_buffer_add(&write_slice_buffer, slice);
       if (write_slice_buffer.count != 1) {
         /* Empty request not handled yet */
@@ -970,7 +982,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       if (write_slice_buffer.count > 0) {
         size_t write_buffer_size;
         create_grpc_frame(&write_slice_buffer, &stream_state->ws.write_buffer,
-                          &write_buffer_size);
+                          &write_buffer_size, stream_op->send_message->flags);
         CRONET_LOG(GPR_DEBUG, "bidirectional_stream_write (%p, %p)", s->cbs,
                    stream_state->ws.write_buffer);
         stream_state->state_callback_received[OP_SEND_MESSAGE] = false;
@@ -1022,6 +1034,9 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
     } else if (stream_state->state_callback_received[OP_FAILED]) {
       grpc_closure_sched(exec_ctx, stream_op->recv_initial_metadata_ready,
                          GRPC_ERROR_NONE);
+    } else if (stream_state->state_op_done[OP_RECV_TRAILING_METADATA]) {
+      grpc_closure_sched(exec_ctx, stream_op->recv_initial_metadata_ready,
+                         GRPC_ERROR_NONE);
     } else {
       grpc_chttp2_incoming_metadata_buffer_publish(
           exec_ctx, &oas->s->state.rs.initial_metadata,
@@ -1066,8 +1081,9 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
           stream_state->rs.remaining_bytes == 0) {
         /* Start a read operation for data */
         stream_state->rs.length_field_received = true;
-        stream_state->rs.length_field = stream_state->rs.remaining_bytes =
-            parse_grpc_header((const uint8_t *)stream_state->rs.read_buffer);
+        parse_grpc_header((const uint8_t *)stream_state->rs.read_buffer,
+                          &stream_state->rs.length_field,
+                          &stream_state->rs.compressed);
         CRONET_LOG(GPR_DEBUG, "length field = %d",
                    stream_state->rs.length_field);
         if (stream_state->rs.length_field > 0) {
@@ -1089,6 +1105,9 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
           grpc_slice_buffer_init(&stream_state->rs.read_slice_buffer);
           grpc_slice_buffer_stream_init(&stream_state->rs.sbs,
                                         &stream_state->rs.read_slice_buffer, 0);
+          if (stream_state->rs.compressed) {
+            stream_state->rs.sbs.base.flags |= GRPC_WRITE_INTERNAL_COMPRESS;
+          }
           *((grpc_byte_buffer **)stream_op->recv_message) =
               (grpc_byte_buffer *)&stream_state->rs.sbs;
           grpc_closure_sched(exec_ctx, stream_op->recv_message_ready,
@@ -1100,6 +1119,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
           stream_state->rs.read_buffer = stream_state->rs.grpc_header_bytes;
           stream_state->rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
           stream_state->rs.received_bytes = 0;
+          stream_state->rs.compressed = false;
           stream_state->rs.length_field_received = false;
           CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
           stream_state->state_op_done[OP_READ_REQ_MADE] =
@@ -1114,6 +1134,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
         stream_state->rs.read_buffer = stream_state->rs.grpc_header_bytes;
         stream_state->rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
         stream_state->rs.received_bytes = 0;
+        stream_state->rs.compressed = false;
         CRONET_LOG(GPR_DEBUG, "bidirectional_stream_read(%p)", s->cbs);
         stream_state->state_op_done[OP_READ_REQ_MADE] =
             true; /* Indicates that at least one read request has been made */
@@ -1137,6 +1158,9 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
                             read_data_slice);
       grpc_slice_buffer_stream_init(&stream_state->rs.sbs,
                                     &stream_state->rs.read_slice_buffer, 0);
+      if (stream_state->rs.compressed) {
+        stream_state->rs.sbs.base.flags = GRPC_WRITE_INTERNAL_COMPRESS;
+      }
       *((grpc_byte_buffer **)stream_op->recv_message) =
           (grpc_byte_buffer *)&stream_state->rs.sbs;
       grpc_closure_sched(exec_ctx, stream_op->recv_message_ready,
@@ -1146,6 +1170,7 @@ static enum e_op_result execute_stream_op(grpc_exec_ctx *exec_ctx,
       /* Do an extra read to trigger on_succeeded() callback in case connection
          is closed */
       stream_state->rs.read_buffer = stream_state->rs.grpc_header_bytes;
+      stream_state->rs.compressed = false;
       stream_state->rs.received_bytes = 0;
       stream_state->rs.remaining_bytes = GRPC_HEADER_SIZE_IN_BYTES;
       stream_state->rs.length_field_received = false;
diff --git a/src/core/lib/channel/connected_channel.c b/src/core/lib/channel/connected_channel.c
index 42ef7b7806..75c68a5534 100644
--- a/src/core/lib/channel/connected_channel.c
+++ b/src/core/lib/channel/connected_channel.c
@@ -90,7 +90,8 @@ static grpc_error *init_call_elem(grpc_exec_ctx *exec_ctx,
       exec_ctx, chand->transport, TRANSPORT_STREAM_FROM_CALL_DATA(calld),
       &args->call_stack->refcount, args->server_transport_data, args->arena);
   return r == 0 ? GRPC_ERROR_NONE
-                : GRPC_ERROR_CREATE("transport stream initialization failed");
+                : GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                      "transport stream initialization failed");
 }
 
 static void set_pollset_or_pollset_set(grpc_exec_ctx *exec_ctx,
diff --git a/src/core/lib/channel/deadline_filter.c b/src/core/lib/channel/deadline_filter.c
index 34114bbebf..ca701ed457 100644
--- a/src/core/lib/channel/deadline_filter.c
+++ b/src/core/lib/channel/deadline_filter.c
@@ -55,9 +55,9 @@ static void timer_callback(grpc_exec_ctx* exec_ctx, void* arg,
   if (error != GRPC_ERROR_CANCELLED) {
     grpc_call_element_signal_error(
         exec_ctx, elem,
-        grpc_error_set_int(GRPC_ERROR_CREATE("Deadline Exceeded"),
-                           GRPC_ERROR_INT_GRPC_STATUS,
-                           GRPC_STATUS_DEADLINE_EXCEEDED));
+        grpc_error_set_int(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Deadline Exceeded"),
+            GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_DEADLINE_EXCEEDED));
   }
   GRPC_CALL_STACK_UNREF(exec_ctx, deadline_state->call_stack, "deadline_timer");
 }
diff --git a/src/core/lib/channel/handshaker.c b/src/core/lib/channel/handshaker.c
index 1b4240bb10..5861fa6f54 100644
--- a/src/core/lib/channel/handshaker.c
+++ b/src/core/lib/channel/handshaker.c
@@ -236,8 +236,9 @@ static void call_next_handshaker(grpc_exec_ctx* exec_ctx, void* arg,
 static void on_timeout(grpc_exec_ctx* exec_ctx, void* arg, grpc_error* error) {
   grpc_handshake_manager* mgr = arg;
   if (error == GRPC_ERROR_NONE) {  // Timer fired, rather than being cancelled.
-    grpc_handshake_manager_shutdown(exec_ctx, mgr,
-                                    GRPC_ERROR_CREATE("Handshake timed out"));
+    grpc_handshake_manager_shutdown(
+        exec_ctx, mgr,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshake timed out"));
   }
   grpc_handshake_manager_unref(exec_ctx, mgr);
 }
diff --git a/src/core/lib/channel/http_client_filter.c b/src/core/lib/channel/http_client_filter.c
index f9d0d689ac..028e9a5d04 100644
--- a/src/core/lib/channel/http_client_filter.c
+++ b/src/core/lib/channel/http_client_filter.c
@@ -108,11 +108,11 @@ static grpc_error *client_filter_incoming_metadata(grpc_exec_ctx *exec_ctx,
       grpc_error *e = grpc_error_set_str(
           grpc_error_set_int(
               grpc_error_set_str(
-                  GRPC_ERROR_CREATE(
+                  GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                       "Received http2 :status header with non-200 OK status"),
-                  GRPC_ERROR_STR_VALUE, val),
+                  GRPC_ERROR_STR_VALUE, grpc_slice_from_copied_string(val)),
               GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_CANCELLED),
-          GRPC_ERROR_STR_GRPC_MESSAGE, msg);
+          GRPC_ERROR_STR_GRPC_MESSAGE, grpc_slice_from_copied_string(msg));
       gpr_free(val);
       gpr_free(msg);
       return e;
diff --git a/src/core/lib/channel/http_server_filter.c b/src/core/lib/channel/http_server_filter.c
index bebd3af335..41a325bc04 100644
--- a/src/core/lib/channel/http_server_filter.c
+++ b/src/core/lib/channel/http_server_filter.c
@@ -101,7 +101,7 @@ static void add_error(const char *error_name, grpc_error **cumulative,
                       grpc_error *new) {
   if (new == GRPC_ERROR_NONE) return;
   if (*cumulative == GRPC_ERROR_NONE) {
-    *cumulative = GRPC_ERROR_CREATE(error_name);
+    *cumulative = GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_name);
   }
   *cumulative = grpc_error_add_child(*cumulative, new);
 }
@@ -125,27 +125,32 @@ static grpc_error *server_filter_incoming_metadata(grpc_exec_ctx *exec_ctx,
       *calld->recv_cacheable_request = true;
     } else {
       add_error(error_name, &error,
-                grpc_attach_md_to_error(GRPC_ERROR_CREATE("Bad header"),
-                                        b->idx.named.method->md));
+                grpc_attach_md_to_error(
+                    GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad header"),
+                    b->idx.named.method->md));
     }
     grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.method);
   } else {
-    add_error(error_name, &error,
-              grpc_error_set_str(GRPC_ERROR_CREATE("Missing header"),
-                                 GRPC_ERROR_STR_KEY, ":method"));
+    add_error(
+        error_name, &error,
+        grpc_error_set_str(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
+            GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":method")));
   }
 
   if (b->idx.named.te != NULL) {
     if (!grpc_mdelem_eq(b->idx.named.te->md, GRPC_MDELEM_TE_TRAILERS)) {
       add_error(error_name, &error,
-                grpc_attach_md_to_error(GRPC_ERROR_CREATE("Bad header"),
-                                        b->idx.named.te->md));
+                grpc_attach_md_to_error(
+                    GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad header"),
+                    b->idx.named.te->md));
     }
     grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.te);
   } else {
     add_error(error_name, &error,
-              grpc_error_set_str(GRPC_ERROR_CREATE("Missing header"),
-                                 GRPC_ERROR_STR_KEY, "te"));
+              grpc_error_set_str(
+                  GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
+                  GRPC_ERROR_STR_KEY, grpc_slice_from_static_string("te")));
   }
 
   if (b->idx.named.scheme != NULL) {
@@ -153,14 +158,17 @@ static grpc_error *server_filter_incoming_metadata(grpc_exec_ctx *exec_ctx,
         !grpc_mdelem_eq(b->idx.named.scheme->md, GRPC_MDELEM_SCHEME_HTTPS) &&
         !grpc_mdelem_eq(b->idx.named.scheme->md, GRPC_MDELEM_SCHEME_GRPC)) {
       add_error(error_name, &error,
-                grpc_attach_md_to_error(GRPC_ERROR_CREATE("Bad header"),
-                                        b->idx.named.scheme->md));
+                grpc_attach_md_to_error(
+                    GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad header"),
+                    b->idx.named.scheme->md));
     }
     grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.scheme);
   } else {
-    add_error(error_name, &error,
-              grpc_error_set_str(GRPC_ERROR_CREATE("Missing header"),
-                                 GRPC_ERROR_STR_KEY, ":scheme"));
+    add_error(
+        error_name, &error,
+        grpc_error_set_str(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
+            GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":scheme")));
   }
 
   if (b->idx.named.content_type != NULL) {
@@ -194,8 +202,9 @@ static grpc_error *server_filter_incoming_metadata(grpc_exec_ctx *exec_ctx,
 
   if (b->idx.named.path == NULL) {
     add_error(error_name, &error,
-              grpc_error_set_str(GRPC_ERROR_CREATE("Missing header"),
-                                 GRPC_ERROR_STR_KEY, ":path"));
+              grpc_error_set_str(
+                  GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
+                  GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":path")));
   }
 
   if (b->idx.named.host != NULL && b->idx.named.authority == NULL) {
@@ -212,9 +221,11 @@ static grpc_error *server_filter_incoming_metadata(grpc_exec_ctx *exec_ctx,
   }
 
   if (b->idx.named.authority == NULL) {
-    add_error(error_name, &error,
-              grpc_error_set_str(GRPC_ERROR_CREATE("Missing header"),
-                                 GRPC_ERROR_STR_KEY, ":authority"));
+    add_error(
+        error_name, &error,
+        grpc_error_set_str(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Missing header"),
+            GRPC_ERROR_STR_KEY, grpc_slice_from_static_string(":authority")));
   }
 
   if (b->idx.named.grpc_payload_bin != NULL) {
diff --git a/src/core/lib/channel/message_size_filter.c b/src/core/lib/channel/message_size_filter.c
index 5ba13fe251..63136650a5 100644
--- a/src/core/lib/channel/message_size_filter.c
+++ b/src/core/lib/channel/message_size_filter.c
@@ -121,8 +121,8 @@ static void recv_message_ready(grpc_exec_ctx* exec_ctx, void* user_data,
                  "Received message larger than max (%u vs. %d)",
                  (*calld->recv_message)->length, calld->max_recv_size);
     grpc_error* new_error = grpc_error_set_int(
-        GRPC_ERROR_CREATE(message_string), GRPC_ERROR_INT_GRPC_STATUS,
-        GRPC_STATUS_INVALID_ARGUMENT);
+        GRPC_ERROR_CREATE_FROM_COPIED_STRING(message_string),
+        GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_INVALID_ARGUMENT);
     if (error == GRPC_ERROR_NONE) {
       error = new_error;
     } else {
@@ -147,9 +147,10 @@ static void start_transport_stream_op(grpc_exec_ctx* exec_ctx,
     gpr_asprintf(&message_string, "Sent message larger than max (%u vs. %d)",
                  op->send_message->length, calld->max_send_size);
     grpc_transport_stream_op_finish_with_failure(
-        exec_ctx, op, grpc_error_set_int(GRPC_ERROR_CREATE(message_string),
-                                         GRPC_ERROR_INT_GRPC_STATUS,
-                                         GRPC_STATUS_INVALID_ARGUMENT));
+        exec_ctx, op,
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(message_string),
+                           GRPC_ERROR_INT_GRPC_STATUS,
+                           GRPC_STATUS_INVALID_ARGUMENT));
     gpr_free(message_string);
     return;
   }
diff --git a/src/core/lib/http/httpcli.c b/src/core/lib/http/httpcli.c
index 6d7aa43b81..453a64b049 100644
--- a/src/core/lib/http/httpcli.c
+++ b/src/core/lib/http/httpcli.c
@@ -126,13 +126,15 @@ static void finish(grpc_exec_ctx *exec_ctx, internal_request *req,
 
 static void append_error(internal_request *req, grpc_error *error) {
   if (req->overall_error == GRPC_ERROR_NONE) {
-    req->overall_error = GRPC_ERROR_CREATE("Failed HTTP/1 client request");
+    req->overall_error =
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed HTTP/1 client request");
   }
   grpc_resolved_address *addr = &req->addresses->addrs[req->next_address - 1];
   char *addr_text = grpc_sockaddr_to_uri(addr);
   req->overall_error = grpc_error_add_child(
       req->overall_error,
-      grpc_error_set_str(error, GRPC_ERROR_STR_TARGET_ADDRESS, addr_text));
+      grpc_error_set_str(error, GRPC_ERROR_STR_TARGET_ADDRESS,
+                         grpc_slice_from_copied_string(addr_text)));
   gpr_free(addr_text);
 }
 
@@ -190,8 +192,8 @@ static void on_handshake_done(grpc_exec_ctx *exec_ctx, void *arg,
   internal_request *req = arg;
 
   if (!ep) {
-    next_address(exec_ctx, req,
-                 GRPC_ERROR_CREATE("Unexplained handshake failure"));
+    next_address(exec_ctx, req, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                    "Unexplained handshake failure"));
     return;
   }
 
@@ -221,8 +223,8 @@ static void next_address(grpc_exec_ctx *exec_ctx, internal_request *req,
   }
   if (req->next_address == req->addresses->naddrs) {
     finish(exec_ctx, req,
-           GRPC_ERROR_CREATE_REFERENCING("Failed HTTP requests to all targets",
-                                         &req->overall_error, 1));
+           GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+               "Failed HTTP requests to all targets", &req->overall_error, 1));
     return;
   }
   addr = &req->addresses->addrs[req->next_address++];
diff --git a/src/core/lib/http/httpcli_security_connector.c b/src/core/lib/http/httpcli_security_connector.c
index 354d2f4a09..be6a6d618a 100644
--- a/src/core/lib/http/httpcli_security_connector.c
+++ b/src/core/lib/http/httpcli_security_connector.c
@@ -95,7 +95,7 @@ static void httpcli_ssl_check_peer(grpc_exec_ctx *exec_ctx,
     char *msg;
     gpr_asprintf(&msg, "Peer name %s is not in peer certificate",
                  c->secure_peer_name);
-    error = GRPC_ERROR_CREATE(msg);
+    error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
   }
   grpc_closure_sched(exec_ctx, on_peer_checked, error);
diff --git a/src/core/lib/http/parser.c b/src/core/lib/http/parser.c
index b9c56c103c..aac506b800 100644
--- a/src/core/lib/http/parser.c
+++ b/src/core/lib/http/parser.c
@@ -54,26 +54,36 @@ static grpc_error *handle_response_line(grpc_http_parser *parser) {
   uint8_t *cur = beg;
   uint8_t *end = beg + parser->cur_line_length;
 
-  if (cur == end || *cur++ != 'H') return GRPC_ERROR_CREATE("Expected 'H'");
-  if (cur == end || *cur++ != 'T') return GRPC_ERROR_CREATE("Expected 'T'");
-  if (cur == end || *cur++ != 'T') return GRPC_ERROR_CREATE("Expected 'T'");
-  if (cur == end || *cur++ != 'P') return GRPC_ERROR_CREATE("Expected 'P'");
-  if (cur == end || *cur++ != '/') return GRPC_ERROR_CREATE("Expected '/'");
-  if (cur == end || *cur++ != '1') return GRPC_ERROR_CREATE("Expected '1'");
-  if (cur == end || *cur++ != '.') return GRPC_ERROR_CREATE("Expected '.'");
+  if (cur == end || *cur++ != 'H')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'H'");
+  if (cur == end || *cur++ != 'T')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'T'");
+  if (cur == end || *cur++ != 'T')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'T'");
+  if (cur == end || *cur++ != 'P')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'P'");
+  if (cur == end || *cur++ != '/')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected '/'");
+  if (cur == end || *cur++ != '1')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected '1'");
+  if (cur == end || *cur++ != '.')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected '.'");
   if (cur == end || *cur < '0' || *cur++ > '1') {
-    return GRPC_ERROR_CREATE("Expected HTTP/1.0 or HTTP/1.1");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Expected HTTP/1.0 or HTTP/1.1");
   }
-  if (cur == end || *cur++ != ' ') return GRPC_ERROR_CREATE("Expected ' '");
+  if (cur == end || *cur++ != ' ')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected ' '");
   if (cur == end || *cur < '1' || *cur++ > '9')
-    return GRPC_ERROR_CREATE("Expected status code");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected status code");
   if (cur == end || *cur < '0' || *cur++ > '9')
-    return GRPC_ERROR_CREATE("Expected status code");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected status code");
   if (cur == end || *cur < '0' || *cur++ > '9')
-    return GRPC_ERROR_CREATE("Expected status code");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected status code");
   parser->http.response->status =
       (cur[-3] - '0') * 100 + (cur[-2] - '0') * 10 + (cur[-1] - '0');
-  if (cur == end || *cur++ != ' ') return GRPC_ERROR_CREATE("Expected ' '");
+  if (cur == end || *cur++ != ' ')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected ' '");
 
   /* we don't really care about the status code message */
 
@@ -89,24 +99,33 @@ static grpc_error *handle_request_line(grpc_http_parser *parser) {
 
   while (cur != end && *cur++ != ' ')
     ;
-  if (cur == end) return GRPC_ERROR_CREATE("No method on HTTP request line");
+  if (cur == end)
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "No method on HTTP request line");
   parser->http.request->method = buf2str(beg, (size_t)(cur - beg - 1));
 
   beg = cur;
   while (cur != end && *cur++ != ' ')
     ;
-  if (cur == end) return GRPC_ERROR_CREATE("No path on HTTP request line");
+  if (cur == end)
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("No path on HTTP request line");
   parser->http.request->path = buf2str(beg, (size_t)(cur - beg - 1));
 
-  if (cur == end || *cur++ != 'H') return GRPC_ERROR_CREATE("Expected 'H'");
-  if (cur == end || *cur++ != 'T') return GRPC_ERROR_CREATE("Expected 'T'");
-  if (cur == end || *cur++ != 'T') return GRPC_ERROR_CREATE("Expected 'T'");
-  if (cur == end || *cur++ != 'P') return GRPC_ERROR_CREATE("Expected 'P'");
-  if (cur == end || *cur++ != '/') return GRPC_ERROR_CREATE("Expected '/'");
+  if (cur == end || *cur++ != 'H')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'H'");
+  if (cur == end || *cur++ != 'T')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'T'");
+  if (cur == end || *cur++ != 'T')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'T'");
+  if (cur == end || *cur++ != 'P')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected 'P'");
+  if (cur == end || *cur++ != '/')
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Expected '/'");
   vers_major = (uint8_t)(*cur++ - '1' + 1);
   ++cur;
   if (cur == end)
-    return GRPC_ERROR_CREATE("End of line in HTTP version string");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "End of line in HTTP version string");
   vers_minor = (uint8_t)(*cur++ - '1' + 1);
 
   if (vers_major == 1) {
@@ -115,18 +134,19 @@ static grpc_error *handle_request_line(grpc_http_parser *parser) {
     } else if (vers_minor == 1) {
       parser->http.request->version = GRPC_HTTP_HTTP11;
     } else {
-      return GRPC_ERROR_CREATE(
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
           "Expected one of HTTP/1.0, HTTP/1.1, or HTTP/2.0");
     }
   } else if (vers_major == 2) {
     if (vers_minor == 0) {
       parser->http.request->version = GRPC_HTTP_HTTP20;
     } else {
-      return GRPC_ERROR_CREATE(
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
           "Expected one of HTTP/1.0, HTTP/1.1, or HTTP/2.0");
     }
   } else {
-    return GRPC_ERROR_CREATE("Expected one of HTTP/1.0, HTTP/1.1, or HTTP/2.0");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Expected one of HTTP/1.0, HTTP/1.1, or HTTP/2.0");
   }
 
   return GRPC_ERROR_NONE;
@@ -139,7 +159,8 @@ static grpc_error *handle_first_line(grpc_http_parser *parser) {
     case GRPC_HTTP_RESPONSE:
       return handle_response_line(parser);
   }
-  GPR_UNREACHABLE_CODE(return GRPC_ERROR_CREATE("Should never reach here"));
+  GPR_UNREACHABLE_CODE(
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Should never reach here"));
 }
 
 static grpc_error *add_header(grpc_http_parser *parser) {
@@ -154,7 +175,8 @@ static grpc_error *add_header(grpc_http_parser *parser) {
   GPR_ASSERT(cur != end);
 
   if (*cur == ' ' || *cur == '\t') {
-    error = GRPC_ERROR_CREATE("Continued header lines not supported yet");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Continued header lines not supported yet");
     goto done;
   }
 
@@ -162,7 +184,8 @@ static grpc_error *add_header(grpc_http_parser *parser) {
     cur++;
   }
   if (cur == end) {
-    error = GRPC_ERROR_CREATE("Didn't find ':' in header string");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Didn't find ':' in header string");
     goto done;
   }
   GPR_ASSERT(cur >= beg);
@@ -222,7 +245,8 @@ static grpc_error *finish_line(grpc_http_parser *parser,
       }
       break;
     case GRPC_HTTP_BODY:
-      GPR_UNREACHABLE_CODE(return GRPC_ERROR_CREATE("Should never reach here"));
+      GPR_UNREACHABLE_CODE(return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+          "Should never reach here"));
   }
 
   parser->cur_line_length = 0;
@@ -240,7 +264,8 @@ static grpc_error *addbyte_body(grpc_http_parser *parser, uint8_t byte) {
     body_length = &parser->http.request->body_length;
     body = &parser->http.request->body;
   } else {
-    GPR_UNREACHABLE_CODE(return GRPC_ERROR_CREATE("Should never reach here"));
+    GPR_UNREACHABLE_CODE(
+        return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Should never reach here"));
   }
 
   if (*body_length == parser->body_capacity) {
@@ -286,7 +311,8 @@ static grpc_error *addbyte(grpc_http_parser *parser, uint8_t byte,
         if (grpc_http1_trace)
           gpr_log(GPR_ERROR, "HTTP header max line length (%d) exceeded",
                   GRPC_HTTP_PARSER_MAX_HEADER_LENGTH);
-        return GRPC_ERROR_CREATE("HTTP header max line length exceeded");
+        return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+            "HTTP header max line length exceeded");
       }
       parser->cur_line[parser->cur_line_length] = byte;
       parser->cur_line_length++;
@@ -347,7 +373,7 @@ grpc_error *grpc_http_parser_parse(grpc_http_parser *parser, grpc_slice slice,
 
 grpc_error *grpc_http_parser_eof(grpc_http_parser *parser) {
   if (parser->state != GRPC_HTTP_BODY) {
-    return GRPC_ERROR_CREATE("Did not finish headers");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Did not finish headers");
   }
   return GRPC_ERROR_NONE;
 }
diff --git a/src/core/lib/iomgr/closure.c b/src/core/lib/iomgr/closure.c
index 509c1ff95d..6633fb68ec 100644
--- a/src/core/lib/iomgr/closure.c
+++ b/src/core/lib/iomgr/closure.c
@@ -33,6 +33,7 @@
 
 #include "src/core/lib/iomgr/closure.h"
 
+#include <assert.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
 
@@ -124,6 +125,7 @@ void grpc_closure_run(grpc_exec_ctx *exec_ctx, grpc_closure *c,
                       grpc_error *error) {
   GPR_TIMER_BEGIN("grpc_closure_run", 0);
   if (c != NULL) {
+    assert(c->cb);
     c->scheduler->vtable->run(exec_ctx, c, error);
   } else {
     GRPC_ERROR_UNREF(error);
@@ -135,6 +137,7 @@ void grpc_closure_sched(grpc_exec_ctx *exec_ctx, grpc_closure *c,
                         grpc_error *error) {
   GPR_TIMER_BEGIN("grpc_closure_sched", 0);
   if (c != NULL) {
+    assert(c->cb);
     c->scheduler->vtable->sched(exec_ctx, c, error);
   } else {
     GRPC_ERROR_UNREF(error);
@@ -146,6 +149,7 @@ void grpc_closure_list_sched(grpc_exec_ctx *exec_ctx, grpc_closure_list *list) {
   grpc_closure *c = list->head;
   while (c != NULL) {
     grpc_closure *next = c->next_data.next;
+    assert(c->cb);
     c->scheduler->vtable->sched(exec_ctx, c, c->error_data.error);
     c = next;
   }
diff --git a/src/core/lib/iomgr/combiner.c b/src/core/lib/iomgr/combiner.c
index fa9966c3a6..2bc476bbef 100644
--- a/src/core/lib/iomgr/combiner.c
+++ b/src/core/lib/iomgr/combiner.c
@@ -33,6 +33,7 @@
 
 #include "src/core/lib/iomgr/combiner.h"
 
+#include <assert.h>
 #include <string.h>
 
 #include <grpc/support/alloc.h>
@@ -216,6 +217,7 @@ static void combiner_exec(grpc_exec_ctx *exec_ctx, grpc_combiner *lock,
       GPR_DEBUG, "C:%p grpc_combiner_execute c=%p cov=%d last=%" PRIdPTR, lock,
       cl, covered_by_poller, last));
   GPR_ASSERT(last & STATE_UNORPHANED);  // ensure lock has not been destroyed
+  assert(cl->cb);
   cl->error_data.scratch =
       pack_error_data((error_data){error, covered_by_poller});
   if (covered_by_poller) {
diff --git a/src/core/lib/iomgr/error.c b/src/core/lib/iomgr/error.c
index 1127fff756..1dbb64e8f3 100644
--- a/src/core/lib/iomgr/error.c
+++ b/src/core/lib/iomgr/error.c
@@ -35,7 +35,6 @@
 
 #include <string.h>
 
-#include <grpc/slice.h>
 #include <grpc/status.h>
 #include <grpc/support/alloc.h>
 #include <grpc/support/log.h>
@@ -287,7 +286,7 @@ static void internal_add_error(grpc_error **err, grpc_error *new) {
 // It is very common to include and extra int and string in an error
 #define SURPLUS_CAPACITY (2 * SLOTS_PER_INT + SLOTS_PER_TIME)
 
-grpc_error *grpc_error_create(const char *file, int line, const char *desc,
+grpc_error *grpc_error_create(grpc_slice file, int line, grpc_slice desc,
                               grpc_error **referencing,
                               size_t num_referencing) {
   GPR_TIMER_BEGIN("grpc_error_create", 0);
@@ -313,14 +312,8 @@ grpc_error *grpc_error_create(const char *file, int line, const char *desc,
   memset(err->times, UINT8_MAX, GRPC_ERROR_TIME_MAX);
 
   internal_set_int(&err, GRPC_ERROR_INT_FILE_LINE, line);
-  internal_set_str(&err, GRPC_ERROR_STR_FILE,
-                   grpc_slice_from_static_string(file));
-  internal_set_str(
-      &err, GRPC_ERROR_STR_DESCRIPTION,
-      grpc_slice_from_copied_buffer(
-          desc,
-          strlen(desc) +
-              1));  // TODO, pull this up.  // TODO(ncteisen), pull this up.
+  internal_set_str(&err, GRPC_ERROR_STR_FILE, file);
+  internal_set_str(&err, GRPC_ERROR_STR_DESCRIPTION, desc);
 
   for (size_t i = 0; i < num_referencing; ++i) {
     if (referencing[i] == GRPC_ERROR_NONE) continue;
@@ -360,7 +353,7 @@ static grpc_error *copy_error_and_unref(grpc_error *in) {
   GPR_TIMER_BEGIN("copy_error_and_unref", 0);
   grpc_error *out;
   if (grpc_error_is_special(in)) {
-    out = GRPC_ERROR_CREATE("unknown");
+    out = GRPC_ERROR_CREATE_FROM_STATIC_STRING("unknown");
     if (in == GRPC_ERROR_NONE) {
       internal_set_str(&out, GRPC_ERROR_STR_DESCRIPTION,
                        grpc_slice_from_static_string("no error"));
@@ -417,7 +410,7 @@ typedef struct {
   const char *msg;
 } special_error_status_map;
 static special_error_status_map error_status_map[] = {
-    {GRPC_ERROR_NONE, GRPC_STATUS_OK, NULL},
+    {GRPC_ERROR_NONE, GRPC_STATUS_OK, ""},
     {GRPC_ERROR_CANCELLED, GRPC_STATUS_CANCELLED, "Cancelled"},
     {GRPC_ERROR_OOM, GRPC_STATUS_RESOURCE_EXHAUSTED, "Out of memory"},
 };
@@ -448,33 +441,33 @@ bool grpc_error_get_int(grpc_error *err, grpc_error_ints which, intptr_t *p) {
 }
 
 grpc_error *grpc_error_set_str(grpc_error *src, grpc_error_strs which,
-                               const char *value) {
+                               grpc_slice str) {
   GPR_TIMER_BEGIN("grpc_error_set_str", 0);
   grpc_error *new = copy_error_and_unref(src);
-  internal_set_str(&new, which,
-                   grpc_slice_from_copied_buffer(
-                       value, strlen(value) + 1));  // TODO, pull this up.
+  internal_set_str(&new, which, str);
   GPR_TIMER_END("grpc_error_set_str", 0);
   return new;
 }
 
-const char *grpc_error_get_str(grpc_error *err, grpc_error_strs which) {
+bool grpc_error_get_str(grpc_error *err, grpc_error_strs which,
+                        grpc_slice *str) {
   if (grpc_error_is_special(err)) {
     if (which == GRPC_ERROR_STR_GRPC_MESSAGE) {
       for (size_t i = 0; i < GPR_ARRAY_SIZE(error_status_map); i++) {
         if (error_status_map[i].error == err) {
-          return error_status_map[i].msg;
+          *str = grpc_slice_from_static_string(error_status_map[i].msg);
+          return true;
         }
       }
     }
-    return NULL;
+    return false;
   }
   uint8_t slot = err->strs[which];
   if (slot != UINT8_MAX) {
-    return (const char *)GRPC_SLICE_START_PTR(
-        *(grpc_slice *)(err->arena + slot));
+    *str = *(grpc_slice *)(err->arena + slot);
+    return true;
   } else {
-    return NULL;
+    return false;
   }
 }
 
@@ -515,13 +508,14 @@ static void append_str(const char *str, char **s, size_t *sz, size_t *cap) {
   }
 }
 
-static void append_esc_str(const char *str, char **s, size_t *sz, size_t *cap) {
+static void append_esc_str(const uint8_t *str, size_t len, char **s, size_t *sz,
+                           size_t *cap) {
   static const char *hex = "0123456789abcdef";
   append_chr('"', s, sz, cap);
-  for (const uint8_t *c = (const uint8_t *)str; *c; c++) {
-    if (*c < 32 || *c >= 127) {
+  for (size_t i = 0; i < len; i++, str++) {
+    if (*str < 32 || *str >= 127) {
       append_chr('\\', s, sz, cap);
-      switch (*c) {
+      switch (*str) {
         case '\b':
           append_chr('b', s, sz, cap);
           break;
@@ -541,12 +535,12 @@ static void append_esc_str(const char *str, char **s, size_t *sz, size_t *cap) {
           append_chr('u', s, sz, cap);
           append_chr('0', s, sz, cap);
           append_chr('0', s, sz, cap);
-          append_chr(hex[*c >> 4], s, sz, cap);
-          append_chr(hex[*c & 0x0f], s, sz, cap);
+          append_chr(hex[*str >> 4], s, sz, cap);
+          append_chr(hex[*str & 0x0f], s, sz, cap);
           break;
       }
     } else {
-      append_chr((char)*c, s, sz, cap);
+      append_chr((char)*str, s, sz, cap);
     }
   }
   append_chr('"', s, sz, cap);
@@ -586,11 +580,12 @@ static char *key_str(grpc_error_strs which) {
   return gpr_strdup(error_str_name(which));
 }
 
-static char *fmt_str(void *p) {
+static char *fmt_str(grpc_slice slice) {
   char *s = NULL;
   size_t sz = 0;
   size_t cap = 0;
-  append_esc_str(p, &s, &sz, &cap);
+  append_esc_str((const uint8_t *)GRPC_SLICE_START_PTR(slice),
+                 GRPC_SLICE_LENGTH(slice), &s, &sz, &cap);
   append_chr(0, &s, &sz, &cap);
   return s;
 }
@@ -599,9 +594,8 @@ static void collect_strs_kvs(grpc_error *err, kv_pairs *kvs) {
   for (size_t which = 0; which < GRPC_ERROR_STR_MAX; ++which) {
     uint8_t slot = err->strs[which];
     if (slot != UINT8_MAX) {
-      append_kv(
-          kvs, key_str((grpc_error_strs)which),
-          fmt_str(GRPC_SLICE_START_PTR(*(grpc_slice *)(err->arena + slot))));
+      append_kv(kvs, key_str((grpc_error_strs)which),
+                fmt_str(*(grpc_slice *)(err->arena + slot)));
     }
   }
 }
@@ -681,7 +675,8 @@ static char *finish_kvs(kv_pairs *kvs) {
   append_chr('{', &s, &sz, &cap);
   for (size_t i = 0; i < kvs->num_kvs; i++) {
     if (i != 0) append_chr(',', &s, &sz, &cap);
-    append_esc_str(kvs->kvs[i].key, &s, &sz, &cap);
+    append_esc_str((const uint8_t *)kvs->kvs[i].key, strlen(kvs->kvs[i].key),
+                   &s, &sz, &cap);
     gpr_free(kvs->kvs[i].key);
     append_chr(':', &s, &sz, &cap);
     append_str(kvs->kvs[i].value, &s, &sz, &cap);
@@ -733,10 +728,14 @@ grpc_error *grpc_os_error(const char *file, int line, int err,
                           const char *call_name) {
   return grpc_error_set_str(
       grpc_error_set_str(
-          grpc_error_set_int(grpc_error_create(file, line, "OS Error", NULL, 0),
-                             GRPC_ERROR_INT_ERRNO, err),
-          GRPC_ERROR_STR_OS_ERROR, strerror(err)),
-      GRPC_ERROR_STR_SYSCALL, call_name);
+          grpc_error_set_int(
+              grpc_error_create(grpc_slice_from_static_string(file), line,
+                                grpc_slice_from_static_string("OS Error"), NULL,
+                                0),
+              GRPC_ERROR_INT_ERRNO, err),
+          GRPC_ERROR_STR_OS_ERROR,
+          grpc_slice_from_static_string(strerror(err))),
+      GRPC_ERROR_STR_SYSCALL, grpc_slice_from_static_string(call_name));
 }
 
 #ifdef GPR_WINDOWS
@@ -745,10 +744,13 @@ grpc_error *grpc_wsa_error(const char *file, int line, int err,
   char *utf8_message = gpr_format_message(err);
   grpc_error *error = grpc_error_set_str(
       grpc_error_set_str(
-          grpc_error_set_int(grpc_error_create(file, line, "OS Error", NULL, 0),
-                             GRPC_ERROR_INT_WSA_ERROR, err),
-          GRPC_ERROR_STR_OS_ERROR, utf8_message),
-      GRPC_ERROR_STR_SYSCALL, call_name);
+          grpc_error_set_int(
+              grpc_error_create(grpc_slice_from_static_string(file), line,
+                                grpc_slice_from_static_string("OS Error"), NULL,
+                                0),
+              GRPC_ERROR_INT_WSA_ERROR, err),
+          GRPC_ERROR_STR_OS_ERROR, grpc_slice_from_copied_string(utf8_message)),
+      GRPC_ERROR_STR_SYSCALL, grpc_slice_from_static_string(call_name));
   gpr_free(utf8_message);
   return error;
 }
diff --git a/src/core/lib/iomgr/error.h b/src/core/lib/iomgr/error.h
index eb953947ae..2a44fcfe25 100644
--- a/src/core/lib/iomgr/error.h
+++ b/src/core/lib/iomgr/error.h
@@ -37,6 +37,7 @@
 #include <stdbool.h>
 #include <stdint.h>
 
+#include <grpc/slice.h>
 #include <grpc/status.h>
 #include <grpc/support/time.h>
 
@@ -45,28 +46,9 @@ extern "C" {
 #endif
 
 /// Opaque representation of an error.
-/// Errors are refcounted objects that represent the result of an operation.
-/// Ownership laws:
-///  if a grpc_error is returned by a function, the caller owns a ref to that
-///    instance
-///  if a grpc_error is passed to a grpc_closure callback function (functions
-///    with the signature:
-///      void (*f)(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error))
-///    then those functions do not own a ref to error (but are free to manually
-///    take a reference).
-///  if a grpc_error is passed to *ANY OTHER FUNCTION* then that function takes
-///    ownership of the error
-/// Errors have:
-///  a set of ints, strings, and timestamps that describe the error
-///  always present are:
-///    GRPC_ERROR_STR_FILE, GRPC_ERROR_INT_FILE_LINE - source location the error
-///      was generated
-///    GRPC_ERROR_STR_DESCRIPTION - a human readable description of the error
-///    GRPC_ERROR_TIME_CREATED - a timestamp indicating when the error happened
-///  an error can also have children; these are other errors that are believed
-///    to have contributed to this one. By accumulating children, we can begin
-///    to root cause high level failures from low level failures, without having
-///    to derive execution paths from log lines
+/// See https://github.com/grpc/grpc/blob/master/doc/core/grpc-error.md for a
+/// full write up of this object.
+
 typedef struct grpc_error grpc_error;
 
 typedef enum {
@@ -156,7 +138,7 @@ typedef enum {
 const char *grpc_error_string(grpc_error *error);
 
 /// Create an error - but use GRPC_ERROR_CREATE instead
-grpc_error *grpc_error_create(const char *file, int line, const char *desc,
+grpc_error *grpc_error_create(grpc_slice file, int line, grpc_slice desc,
                               grpc_error **referencing, size_t num_referencing);
 /// Create an error (this is the preferred way of generating an error that is
 ///   not due to a system call - for system calls, use GRPC_OS_ERROR or
@@ -166,13 +148,21 @@ grpc_error *grpc_error_create(const char *file, int line, const char *desc,
 /// err = grpc_error_create(x, y, z, r, nr) is equivalent to:
 ///   err = grpc_error_create(x, y, z, NULL, 0);
 ///   for (i=0; i<nr; i++) err = grpc_error_add_child(err, r[i]);
-#define GRPC_ERROR_CREATE(desc) \
-  grpc_error_create(__FILE__, __LINE__, desc, NULL, 0)
+#define GRPC_ERROR_CREATE_FROM_STATIC_STRING(desc)                     \
+  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__, \
+                    grpc_slice_from_static_string(desc), NULL, 0)
+#define GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc)                     \
+  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__, \
+                    grpc_slice_from_copied_string(desc), NULL, 0)
 
 // Create an error that references some other errors. This function adds a
 // reference to each error in errs - it does not consume an existing reference
-#define GRPC_ERROR_CREATE_REFERENCING(desc, errs, count) \
-  grpc_error_create(__FILE__, __LINE__, desc, errs, count)
+#define GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(desc, errs, count) \
+  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__,      \
+                    grpc_slice_from_static_string(desc), errs, count)
+#define GRPC_ERROR_CREATE_REFERENCING_FROM_COPIED_STRING(desc, errs, count) \
+  grpc_error_create(grpc_slice_from_static_string(__FILE__), __LINE__,      \
+                    grpc_slice_from_copied_string(desc), errs, count)
 
 //#define GRPC_ERROR_REFCOUNT_DEBUG
 #ifdef GRPC_ERROR_REFCOUNT_DEBUG
@@ -194,10 +184,11 @@ grpc_error *grpc_error_set_int(grpc_error *src, grpc_error_ints which,
                                intptr_t value) GRPC_MUST_USE_RESULT;
 bool grpc_error_get_int(grpc_error *error, grpc_error_ints which, intptr_t *p);
 grpc_error *grpc_error_set_str(grpc_error *src, grpc_error_strs which,
-                               const char *value) GRPC_MUST_USE_RESULT;
-/// Returns NULL if the specified string is not set.
-/// Caller does NOT own return value.
-const char *grpc_error_get_str(grpc_error *error, grpc_error_strs which);
+                               grpc_slice str) GRPC_MUST_USE_RESULT;
+/// Returns false if the specified string is not set.
+/// Caller does NOT own the slice.
+bool grpc_error_get_str(grpc_error *error, grpc_error_strs which,
+                        grpc_slice *s);
 
 /// Add a child error: an error that is believed to have contributed to this
 /// error occurring. Allows root causing high level errors from lower level
diff --git a/src/core/lib/iomgr/ev_epoll_linux.c b/src/core/lib/iomgr/ev_epoll_linux.c
index 11208b9ad1..1924e76f13 100644
--- a/src/core/lib/iomgr/ev_epoll_linux.c
+++ b/src/core/lib/iomgr/ev_epoll_linux.c
@@ -321,7 +321,7 @@ static bool append_error(grpc_error **composite, grpc_error *error,
                          const char *desc) {
   if (error == GRPC_ERROR_NONE) return true;
   if (*composite == GRPC_ERROR_NONE) {
-    *composite = GRPC_ERROR_CREATE(desc);
+    *composite = GRPC_ERROR_CREATE_FROM_COPIED_STRING(desc);
   }
   *composite = grpc_error_add_child(*composite, error);
   return false;
@@ -1146,9 +1146,9 @@ static void notify_on(grpc_exec_ctx *exec_ctx, grpc_fd *fd, gpr_atm *state,
            schedule the closure with the shutdown error */
         if ((curr & FD_SHUTDOWN_BIT) > 0) {
           grpc_error *shutdown_err = (grpc_error *)(curr & ~FD_SHUTDOWN_BIT);
-          grpc_closure_sched(
-              exec_ctx, closure,
-              GRPC_ERROR_CREATE_REFERENCING("FD Shutdown", &shutdown_err, 1));
+          grpc_closure_sched(exec_ctx, closure,
+                             GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                                 "FD Shutdown", &shutdown_err, 1));
           return;
         }
 
@@ -1203,9 +1203,9 @@ static void set_shutdown(grpc_exec_ctx *exec_ctx, grpc_fd *fd, gpr_atm *state,
            notify_on to ensure that the closure it schedules 'happens-after'
            the set_shutdown is called on the fd */
         if (gpr_atm_rel_cas(state, curr, new_state)) {
-          grpc_closure_sched(
-              exec_ctx, (grpc_closure *)curr,
-              GRPC_ERROR_CREATE_REFERENCING("FD Shutdown", &shutdown_err, 1));
+          grpc_closure_sched(exec_ctx, (grpc_closure *)curr,
+                             GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                                 "FD Shutdown", &shutdown_err, 1));
           return;
         }
 
diff --git a/src/core/lib/iomgr/ev_poll_posix.c b/src/core/lib/iomgr/ev_poll_posix.c
index 5ddd5313e2..ca6e855611 100644
--- a/src/core/lib/iomgr/ev_poll_posix.c
+++ b/src/core/lib/iomgr/ev_poll_posix.c
@@ -451,14 +451,16 @@ static grpc_error *fd_shutdown_error(grpc_fd *fd) {
   if (!fd->shutdown) {
     return GRPC_ERROR_NONE;
   } else {
-    return GRPC_ERROR_CREATE_REFERENCING("FD shutdown", &fd->shutdown_error, 1);
+    return GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+        "FD shutdown", &fd->shutdown_error, 1);
   }
 }
 
 static void notify_on_locked(grpc_exec_ctx *exec_ctx, grpc_fd *fd,
                              grpc_closure **st, grpc_closure *closure) {
   if (fd->shutdown) {
-    grpc_closure_sched(exec_ctx, closure, GRPC_ERROR_CREATE("FD shutdown"));
+    grpc_closure_sched(exec_ctx, closure,
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING("FD shutdown"));
   } else if (*st == CLOSURE_NOT_READY) {
     /* not ready ==> switch to a waiting state by setting the closure */
     *st = closure;
@@ -696,7 +698,7 @@ static void push_front_worker(grpc_pollset *p, grpc_pollset_worker *worker) {
 static void kick_append_error(grpc_error **composite, grpc_error *error) {
   if (error == GRPC_ERROR_NONE) return;
   if (*composite == GRPC_ERROR_NONE) {
-    *composite = GRPC_ERROR_CREATE("Kick Failure");
+    *composite = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Kick Failure");
   }
   *composite = grpc_error_add_child(*composite, error);
 }
@@ -859,7 +861,7 @@ static void finish_shutdown(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset) {
 static void work_combine_error(grpc_error **composite, grpc_error *error) {
   if (error == GRPC_ERROR_NONE) return;
   if (*composite == GRPC_ERROR_NONE) {
-    *composite = GRPC_ERROR_CREATE("pollset_work");
+    *composite = GRPC_ERROR_CREATE_FROM_STATIC_STRING("pollset_work");
   }
   *composite = grpc_error_add_child(*composite, error);
 }
@@ -1421,7 +1423,7 @@ static int cvfd_poll(struct pollfd *fds, nfds_t nfds, int timeout) {
     g_cvfds.pollcount++;
     opt = gpr_thd_options_default();
     gpr_thd_options_set_detached(&opt);
-    gpr_thd_new(&t_id, &run_poll, pargs, &opt);
+    GPR_ASSERT(gpr_thd_new(&t_id, &run_poll, pargs, &opt));
     // We want the poll() thread to trigger the deadline, so wait forever here
     gpr_cv_wait(pollcv, &g_cvfds.mu, gpr_inf_future(GPR_CLOCK_MONOTONIC));
     if (gpr_atm_no_barrier_load(&pargs->status) == COMPLETED) {
diff --git a/src/core/lib/iomgr/executor.c b/src/core/lib/iomgr/executor.c
index a5b62aa888..ae3e2eabc3 100644
--- a/src/core/lib/iomgr/executor.c
+++ b/src/core/lib/iomgr/executor.c
@@ -115,8 +115,8 @@ static void maybe_spawn_locked() {
   /* All previous instances of the thread should have been joined at this point.
    * Spawn time! */
   g_executor.busy = 1;
-  gpr_thd_new(&g_executor.tid, closure_exec_thread_func, NULL,
-              &g_executor.options);
+  GPR_ASSERT(gpr_thd_new(&g_executor.tid, closure_exec_thread_func, NULL,
+                         &g_executor.options));
   g_executor.pending_join = 1;
 }
 
diff --git a/src/core/lib/iomgr/load_file.c b/src/core/lib/iomgr/load_file.c
index f40c8b28cc..208f74e20c 100644
--- a/src/core/lib/iomgr/load_file.c
+++ b/src/core/lib/iomgr/load_file.c
@@ -78,9 +78,12 @@ end:
   *output = result;
   if (file != NULL) fclose(file);
   if (error != GRPC_ERROR_NONE) {
-    grpc_error *error_out = grpc_error_set_str(
-        GRPC_ERROR_CREATE_REFERENCING("Failed to load file", &error, 1),
-        GRPC_ERROR_STR_FILENAME, filename);
+    grpc_error *error_out =
+        grpc_error_set_str(GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                               "Failed to load file", &error, 1),
+                           GRPC_ERROR_STR_FILENAME,
+                           grpc_slice_from_copied_string(
+                               filename));  // TODO(ncteisen), always static?
     GRPC_ERROR_UNREF(error);
     error = error_out;
   }
diff --git a/src/core/lib/iomgr/resolve_address_posix.c b/src/core/lib/iomgr/resolve_address_posix.c
index 50e470d149..d0ede0f2d5 100644
--- a/src/core/lib/iomgr/resolve_address_posix.c
+++ b/src/core/lib/iomgr/resolve_address_posix.c
@@ -73,14 +73,16 @@ static grpc_error *blocking_resolve_address_impl(
   /* parse name, splitting it into host and port parts */
   gpr_split_host_port(name, &host, &port);
   if (host == NULL) {
-    err = grpc_error_set_str(GRPC_ERROR_CREATE("unparseable host:port"),
-                             GRPC_ERROR_STR_TARGET_ADDRESS, name);
+    err = grpc_error_set_str(
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("unparseable host:port"),
+        GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(name));
     goto done;
   }
   if (port == NULL) {
     if (default_port == NULL) {
-      err = grpc_error_set_str(GRPC_ERROR_CREATE("no port in name"),
-                               GRPC_ERROR_STR_TARGET_ADDRESS, name);
+      err = grpc_error_set_str(
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("no port in name"),
+          GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(name));
       goto done;
     }
     port = gpr_strdup(default_port);
@@ -112,11 +114,15 @@ static grpc_error *blocking_resolve_address_impl(
   if (s != 0) {
     err = grpc_error_set_str(
         grpc_error_set_str(
-            grpc_error_set_str(grpc_error_set_int(GRPC_ERROR_CREATE("OS Error"),
-                                                  GRPC_ERROR_INT_ERRNO, s),
-                               GRPC_ERROR_STR_OS_ERROR, gai_strerror(s)),
-            GRPC_ERROR_STR_SYSCALL, "getaddrinfo"),
-        GRPC_ERROR_STR_TARGET_ADDRESS, name);
+            grpc_error_set_str(
+                grpc_error_set_int(
+                    GRPC_ERROR_CREATE_FROM_STATIC_STRING("OS Error"),
+                    GRPC_ERROR_INT_ERRNO, s),
+                GRPC_ERROR_STR_OS_ERROR,
+                grpc_slice_from_static_string(gai_strerror(s))),
+            GRPC_ERROR_STR_SYSCALL,
+            grpc_slice_from_static_string("getaddrinfo")),
+        GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(name));
     goto done;
   }
 
diff --git a/src/core/lib/iomgr/resolve_address_uv.c b/src/core/lib/iomgr/resolve_address_uv.c
index 4d715be94c..102d1aa290 100644
--- a/src/core/lib/iomgr/resolve_address_uv.c
+++ b/src/core/lib/iomgr/resolve_address_uv.c
@@ -92,9 +92,10 @@ static grpc_error *handle_addrinfo_result(int status, struct addrinfo *result,
   if (status != 0) {
     grpc_error *error;
     *addresses = NULL;
-    error = GRPC_ERROR_CREATE("getaddrinfo failed");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("getaddrinfo failed");
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, uv_strerror(status));
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string(uv_strerror(status)));
     return error;
   }
   (*addresses) = gpr_malloc(sizeof(grpc_resolved_addresses));
@@ -153,7 +154,7 @@ static grpc_error *try_split_host_port(const char *name,
   if (*host == NULL) {
     char *msg;
     gpr_asprintf(&msg, "unparseable host:port: '%s'", name);
-    error = GRPC_ERROR_CREATE(msg);
+    error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return error;
   }
@@ -162,7 +163,7 @@ static grpc_error *try_split_host_port(const char *name,
     if (default_port == NULL) {
       char *msg;
       gpr_asprintf(&msg, "no port in name '%s'", name);
-      error = GRPC_ERROR_CREATE(msg);
+      error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
       gpr_free(msg);
       return error;
     }
@@ -262,8 +263,9 @@ static void resolve_address_impl(grpc_exec_ctx *exec_ctx, const char *name,
 
   if (s != 0) {
     *addrs = NULL;
-    err = GRPC_ERROR_CREATE("getaddrinfo failed");
-    err = grpc_error_set_str(err, GRPC_ERROR_STR_OS_ERROR, uv_strerror(s));
+    err = GRPC_ERROR_CREATE_FROM_STATIC_STRING("getaddrinfo failed");
+    err = grpc_error_set_str(err, GRPC_ERROR_STR_OS_ERROR,
+                             grpc_slice_from_static_string(uv_strerror(s)));
     grpc_closure_sched(exec_ctx, on_done, err);
     gpr_free(r);
     gpr_free(req);
diff --git a/src/core/lib/iomgr/resolve_address_windows.c b/src/core/lib/iomgr/resolve_address_windows.c
index 2439ce3cb7..22eca1fd3b 100644
--- a/src/core/lib/iomgr/resolve_address_windows.c
+++ b/src/core/lib/iomgr/resolve_address_windows.c
@@ -78,7 +78,7 @@ static grpc_error *blocking_resolve_address_impl(
   if (host == NULL) {
     char *msg;
     gpr_asprintf(&msg, "unparseable host:port: '%s'", name);
-    error = GRPC_ERROR_CREATE(msg);
+    error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     goto done;
   }
@@ -86,7 +86,7 @@ static grpc_error *blocking_resolve_address_impl(
     if (default_port == NULL) {
       char *msg;
       gpr_asprintf(&msg, "no port in name '%s'", name);
-      error = GRPC_ERROR_CREATE(msg);
+      error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
       gpr_free(msg);
       goto done;
     }
diff --git a/src/core/lib/iomgr/socket_utils_common_posix.c b/src/core/lib/iomgr/socket_utils_common_posix.c
index 88e9ade253..b69c924d4a 100644
--- a/src/core/lib/iomgr/socket_utils_common_posix.c
+++ b/src/core/lib/iomgr/socket_utils_common_posix.c
@@ -90,7 +90,7 @@ grpc_error *grpc_set_socket_no_sigpipe_if_possible(int fd) {
     return GRPC_OS_ERROR(errno, "getsockopt(SO_NOSIGPIPE)");
   }
   if ((newval != 0) != (val != 0)) {
-    return GRPC_ERROR_CREATE("Failed to set SO_NOSIGPIPE");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set SO_NOSIGPIPE");
   }
 #endif
   return GRPC_ERROR_NONE;
@@ -164,7 +164,7 @@ grpc_error *grpc_set_socket_reuse_addr(int fd, int reuse) {
     return GRPC_OS_ERROR(errno, "getsockopt(SO_REUSEADDR)");
   }
   if ((newval != 0) != val) {
-    return GRPC_ERROR_CREATE("Failed to set SO_REUSEADDR");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set SO_REUSEADDR");
   }
 
   return GRPC_ERROR_NONE;
@@ -173,7 +173,8 @@ grpc_error *grpc_set_socket_reuse_addr(int fd, int reuse) {
 /* set a socket to reuse old addresses */
 grpc_error *grpc_set_socket_reuse_port(int fd, int reuse) {
 #ifndef SO_REUSEPORT
-  return GRPC_ERROR_CREATE("SO_REUSEPORT unavailable on compiling system");
+  return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+      "SO_REUSEPORT unavailable on compiling system");
 #else
   int val = (reuse != 0);
   int newval;
@@ -185,7 +186,7 @@ grpc_error *grpc_set_socket_reuse_port(int fd, int reuse) {
     return GRPC_OS_ERROR(errno, "getsockopt(SO_REUSEPORT)");
   }
   if ((newval != 0) != val) {
-    return GRPC_ERROR_CREATE("Failed to set SO_REUSEPORT");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set SO_REUSEPORT");
   }
 
   return GRPC_ERROR_NONE;
@@ -204,7 +205,7 @@ grpc_error *grpc_set_socket_low_latency(int fd, int low_latency) {
     return GRPC_OS_ERROR(errno, "getsockopt(TCP_NODELAY)");
   }
   if ((newval != 0) != val) {
-    return GRPC_ERROR_CREATE("Failed to set TCP_NODELAY");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set TCP_NODELAY");
   }
   return GRPC_ERROR_NONE;
 }
@@ -213,7 +214,7 @@ grpc_error *grpc_set_socket_low_latency(int fd, int low_latency) {
 grpc_error *grpc_set_socket_with_mutator(int fd, grpc_socket_mutator *mutator) {
   GPR_ASSERT(mutator);
   if (!grpc_socket_mutator_mutate_fd(mutator, fd)) {
-    return GRPC_ERROR_CREATE("grpc_socket_mutator failed.");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("grpc_socket_mutator failed.");
   }
   return GRPC_ERROR_NONE;
 }
@@ -268,7 +269,8 @@ static grpc_error *error_for_fd(int fd, const grpc_resolved_address *addr) {
   char *addr_str;
   grpc_sockaddr_to_string(&addr_str, addr, 0);
   grpc_error *err = grpc_error_set_str(GRPC_OS_ERROR(errno, "socket"),
-                                       GRPC_ERROR_STR_TARGET_ADDRESS, addr_str);
+                                       GRPC_ERROR_STR_TARGET_ADDRESS,
+                                       grpc_slice_from_copied_string(addr_str));
   gpr_free(addr_str);
   return err;
 }
diff --git a/src/core/lib/iomgr/tcp_client_posix.c b/src/core/lib/iomgr/tcp_client_posix.c
index 0144192b71..a108b10da6 100644
--- a/src/core/lib/iomgr/tcp_client_posix.c
+++ b/src/core/lib/iomgr/tcp_client_posix.c
@@ -121,8 +121,8 @@ static void tc_on_alarm(grpc_exec_ctx *exec_ctx, void *acp, grpc_error *error) {
   }
   gpr_mu_lock(&ac->mu);
   if (ac->fd != NULL) {
-    grpc_fd_shutdown(exec_ctx, ac->fd,
-                     GRPC_ERROR_CREATE("connect() timed out"));
+    grpc_fd_shutdown(exec_ctx, ac->fd, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                           "connect() timed out"));
   }
   done = (--ac->refs == 0);
   gpr_mu_unlock(&ac->mu);
@@ -191,7 +191,8 @@ static void on_writable(grpc_exec_ctx *exec_ctx, void *acp, grpc_error *error) {
   gpr_mu_lock(&ac->mu);
   if (error != GRPC_ERROR_NONE) {
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, "Timeout occurred");
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string("Timeout occurred"));
     goto finish;
   }
 
@@ -252,12 +253,17 @@ finish:
   gpr_mu_unlock(&ac->mu);
   if (error != GRPC_ERROR_NONE) {
     char *error_descr;
-    gpr_asprintf(&error_descr, "Failed to connect to remote host: %s",
-                 grpc_error_get_str(error, GRPC_ERROR_STR_DESCRIPTION));
-    error = grpc_error_set_str(error, GRPC_ERROR_STR_DESCRIPTION, error_descr);
+    grpc_slice str;
+    bool ret = grpc_error_get_str(error, GRPC_ERROR_STR_DESCRIPTION, &str);
+    GPR_ASSERT(ret);
+    char *desc = grpc_slice_to_c_string(str);
+    gpr_asprintf(&error_descr, "Failed to connect to remote host: %s", desc);
+    error = grpc_error_set_str(error, GRPC_ERROR_STR_DESCRIPTION,
+                               grpc_slice_from_copied_string(error_descr));
     gpr_free(error_descr);
-    error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_TARGET_ADDRESS, ac->addr_str);
+    gpr_free(desc);
+    error = grpc_error_set_str(error, GRPC_ERROR_STR_TARGET_ADDRESS,
+                               grpc_slice_from_copied_string(ac->addr_str));
   }
   if (done) {
     gpr_mu_destroy(&ac->mu);
diff --git a/src/core/lib/iomgr/tcp_client_uv.c b/src/core/lib/iomgr/tcp_client_uv.c
index 618483d9cb..682c24ed56 100644
--- a/src/core/lib/iomgr/tcp_client_uv.c
+++ b/src/core/lib/iomgr/tcp_client_uv.c
@@ -100,17 +100,21 @@ static void uv_tc_on_connect(uv_connect_t *req, int status) {
     *connect->endpoint = grpc_tcp_create(
         connect->tcp_handle, connect->resource_quota, connect->addr_name);
   } else {
-    error = GRPC_ERROR_CREATE("Failed to connect to remote host");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Failed to connect to remote host");
     error = grpc_error_set_int(error, GRPC_ERROR_INT_ERRNO, -status);
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, uv_strerror(status));
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string(uv_strerror(status)));
     if (status == UV_ECANCELED) {
-      error = grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
-                                 "Timeout occurred");
+      error =
+          grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                             grpc_slice_from_static_string("Timeout occurred"));
       // This should only happen if the handle is already closed
     } else {
-      error = grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
-                                 uv_strerror(status));
+      error = grpc_error_set_str(
+          error, GRPC_ERROR_STR_OS_ERROR,
+          grpc_slice_from_static_string(uv_strerror(status)));
       uv_close((uv_handle_t *)connect->tcp_handle, tcp_close_callback);
     }
   }
diff --git a/src/core/lib/iomgr/tcp_client_windows.c b/src/core/lib/iomgr/tcp_client_windows.c
index c8dc9e64bd..a356564766 100644
--- a/src/core/lib/iomgr/tcp_client_windows.c
+++ b/src/core/lib/iomgr/tcp_client_windows.c
@@ -123,7 +123,7 @@ static void on_connect(grpc_exec_ctx *exec_ctx, void *acp, grpc_error *error) {
         socket = NULL;
       }
     } else {
-      error = GRPC_ERROR_CREATE("socket is null");
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("socket is null");
     }
   }
 
@@ -238,8 +238,9 @@ failure:
   GPR_ASSERT(error != GRPC_ERROR_NONE);
   char *target_uri = grpc_sockaddr_to_uri(addr);
   grpc_error *final_error = grpc_error_set_str(
-      GRPC_ERROR_CREATE_REFERENCING("Failed to connect", &error, 1),
-      GRPC_ERROR_STR_TARGET_ADDRESS, target_uri);
+      GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING("Failed to connect",
+                                                       &error, 1),
+      GRPC_ERROR_STR_TARGET_ADDRESS, grpc_slice_from_copied_string(target_uri));
   GRPC_ERROR_UNREF(error);
   if (socket != NULL) {
     grpc_winsocket_destroy(socket);
diff --git a/src/core/lib/iomgr/tcp_posix.c b/src/core/lib/iomgr/tcp_posix.c
index a4381f8fc9..4d7cf3ff51 100644
--- a/src/core/lib/iomgr/tcp_posix.c
+++ b/src/core/lib/iomgr/tcp_posix.c
@@ -111,7 +111,8 @@ typedef struct {
 static grpc_error *tcp_annotate_error(grpc_error *src_error, grpc_tcp *tcp) {
   return grpc_error_set_str(
       grpc_error_set_int(src_error, GRPC_ERROR_INT_FD, tcp->fd),
-      GRPC_ERROR_STR_TARGET_ADDRESS, tcp->peer_string);
+      GRPC_ERROR_STR_TARGET_ADDRESS,
+      grpc_slice_from_copied_string(tcp->peer_string));
 }
 
 static void tcp_handle_read(grpc_exec_ctx *exec_ctx, void *arg /* grpc_tcp */,
@@ -246,8 +247,10 @@ static void tcp_do_read(grpc_exec_ctx *exec_ctx, grpc_tcp *tcp) {
   } else if (read_bytes == 0) {
     /* 0 read size ==> end of stream */
     grpc_slice_buffer_reset_and_unref_internal(exec_ctx, tcp->incoming_buffer);
-    call_read_cb(exec_ctx, tcp,
-                 tcp_annotate_error(GRPC_ERROR_CREATE("Socket closed"), tcp));
+    call_read_cb(
+        exec_ctx, tcp,
+        tcp_annotate_error(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Socket closed"), tcp));
     TCP_UNREF(exec_ctx, tcp, "read");
   } else {
     GPR_ASSERT((size_t)read_bytes <= tcp->incoming_buffer->length);
@@ -464,10 +467,12 @@ static void tcp_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
 
   if (buf->length == 0) {
     GPR_TIMER_END("tcp_write", 0);
-    grpc_closure_sched(exec_ctx, cb,
-                       grpc_fd_is_shutdown(tcp->em_fd)
-                           ? tcp_annotate_error(GRPC_ERROR_CREATE("EOF"), tcp)
-                           : GRPC_ERROR_NONE);
+    grpc_closure_sched(
+        exec_ctx, cb,
+        grpc_fd_is_shutdown(tcp->em_fd)
+            ? tcp_annotate_error(GRPC_ERROR_CREATE_FROM_STATIC_STRING("EOF"),
+                                 tcp)
+            : GRPC_ERROR_NONE);
     return;
   }
   tcp->outgoing_buffer = buf;
diff --git a/src/core/lib/iomgr/tcp_server_posix.c b/src/core/lib/iomgr/tcp_server_posix.c
index e242631fc0..e1efbd414f 100644
--- a/src/core/lib/iomgr/tcp_server_posix.c
+++ b/src/core/lib/iomgr/tcp_server_posix.c
@@ -100,8 +100,8 @@ grpc_error *grpc_tcp_server_create(grpc_exec_ctx *exec_ctx,
       } else {
         grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
-        return GRPC_ERROR_CREATE(GRPC_ARG_ALLOW_REUSEPORT
-                                 " must be an integer");
+        return GRPC_ERROR_CREATE_FROM_STATIC_STRING(GRPC_ARG_ALLOW_REUSEPORT
+                                                    " must be an integer");
       }
     } else if (0 == strcmp(GRPC_ARG_RESOURCE_QUOTA, args->args[i].key)) {
       if (args->args[i].type == GRPC_ARG_POINTER) {
@@ -111,8 +111,8 @@ grpc_error *grpc_tcp_server_create(grpc_exec_ctx *exec_ctx,
       } else {
         grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
-        return GRPC_ERROR_CREATE(GRPC_ARG_RESOURCE_QUOTA
-                                 " must be a pointer to a buffer pool");
+        return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+            GRPC_ARG_RESOURCE_QUOTA " must be a pointer to a buffer pool");
       }
     } else if (0 == strcmp(GRPC_ARG_EXPAND_WILDCARD_ADDRS, args->args[i].key)) {
       if (args->args[i].type == GRPC_ARG_INTEGER) {
@@ -120,8 +120,8 @@ grpc_error *grpc_tcp_server_create(grpc_exec_ctx *exec_ctx,
       } else {
         grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
-        return GRPC_ERROR_CREATE(GRPC_ARG_EXPAND_WILDCARD_ADDRS
-                                 " must be an integer");
+        return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+            GRPC_ARG_EXPAND_WILDCARD_ADDRS " must be an integer");
       }
     }
   }
@@ -216,8 +216,8 @@ static void tcp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_tcp_server *s) {
   if (s->active_ports) {
     grpc_tcp_listener *sp;
     for (sp = s->head; sp; sp = sp->next) {
-      grpc_fd_shutdown(exec_ctx, sp->emfd,
-                       GRPC_ERROR_CREATE("Server destroyed"));
+      grpc_fd_shutdown(exec_ctx, sp->emfd, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                               "Server destroyed"));
     }
     gpr_mu_unlock(&s->mu);
   } else {
@@ -366,8 +366,8 @@ static grpc_error *add_wildcard_addrs_to_server(grpc_tcp_server *s,
     }
     return GRPC_ERROR_NONE;
   } else {
-    grpc_error *root_err =
-        GRPC_ERROR_CREATE("Failed to add any wildcard listeners");
+    grpc_error *root_err = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Failed to add any wildcard listeners");
     GPR_ASSERT(v6_err != GRPC_ERROR_NONE && v4_err != GRPC_ERROR_NONE);
     root_err = grpc_error_add_child(root_err, v6_err);
     root_err = grpc_error_add_child(root_err, v4_err);
@@ -587,7 +587,7 @@ void grpc_tcp_server_shutdown_listeners(grpc_exec_ctx *exec_ctx,
     grpc_tcp_listener *sp;
     for (sp = s->head; sp; sp = sp->next) {
       grpc_fd_shutdown(exec_ctx, sp->emfd,
-                       GRPC_ERROR_CREATE("Server shutdown"));
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING("Server shutdown"));
     }
   }
   gpr_mu_unlock(&s->mu);
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_common.c b/src/core/lib/iomgr/tcp_server_utils_posix_common.c
index e45e27d5ab..283b92b0a2 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_common.c
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_common.c
@@ -210,9 +210,10 @@ error:
   if (fd >= 0) {
     close(fd);
   }
-  grpc_error *ret = grpc_error_set_int(
-      GRPC_ERROR_CREATE_REFERENCING("Unable to configure socket", &err, 1),
-      GRPC_ERROR_INT_FD, fd);
+  grpc_error *ret =
+      grpc_error_set_int(GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                             "Unable to configure socket", &err, 1),
+                         GRPC_ERROR_INT_FD, fd);
   GRPC_ERROR_UNREF(err);
   return ret;
 }
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c b/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c
index 6354a6bdc1..2078a68126 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_ifaddrs.c
@@ -94,7 +94,8 @@ static grpc_error *get_unused_port(int *port) {
   }
   close(fd);
   *port = grpc_sockaddr_get_port(&wild);
-  return *port <= 0 ? GRPC_ERROR_CREATE("Bad port") : GRPC_ERROR_NONE;
+  return *port <= 0 ? GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad port")
+                    : GRPC_ERROR_NONE;
 }
 
 grpc_error *grpc_tcp_server_add_all_local_addrs(grpc_tcp_server *s,
@@ -114,7 +115,7 @@ grpc_error *grpc_tcp_server_add_all_local_addrs(grpc_tcp_server *s,
     if ((err = get_unused_port(&requested_port)) != GRPC_ERROR_NONE) {
       return err;
     } else if (requested_port <= 0) {
-      return GRPC_ERROR_CREATE("Bad get_unused_port()");
+      return GRPC_ERROR_CREATE_FROM_STATIC_STRING("Bad get_unused_port()");
     }
     gpr_log(GPR_DEBUG, "Picked unused port %d", requested_port);
   }
@@ -139,7 +140,7 @@ grpc_error *grpc_tcp_server_add_all_local_addrs(grpc_tcp_server *s,
     memcpy(addr.addr, ifa_it->ifa_addr, addr.len);
     if (!grpc_sockaddr_set_port(&addr, requested_port)) {
       /* Should never happen, because we check sa_family above. */
-      err = GRPC_ERROR_CREATE("Failed to set port");
+      err = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to set port");
       break;
     }
     if (grpc_sockaddr_to_string(&addr_str, &addr, 0) < 0) {
@@ -163,7 +164,7 @@ grpc_error *grpc_tcp_server_add_all_local_addrs(grpc_tcp_server *s,
       if (gpr_asprintf(&err_str, "Failed to add listener: %s", addr_str) < 0) {
         err_str = gpr_strdup("Failed to add listener");
       }
-      root_err = GRPC_ERROR_CREATE(err_str);
+      root_err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(err_str);
       gpr_free(err_str);
       gpr_free(addr_str);
       err = grpc_error_add_child(root_err, err);
@@ -183,7 +184,7 @@ grpc_error *grpc_tcp_server_add_all_local_addrs(grpc_tcp_server *s,
   if (err != GRPC_ERROR_NONE) {
     return err;
   } else if (sp == NULL) {
-    return GRPC_ERROR_CREATE("No local addresses");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING("No local addresses");
   } else {
     *out_port = sp->port;
     return GRPC_ERROR_NONE;
diff --git a/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c b/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c
index 95c3198be6..d6a1a0693e 100644
--- a/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c
+++ b/src/core/lib/iomgr/tcp_server_utils_posix_noifaddrs.c
@@ -41,7 +41,7 @@ grpc_error *grpc_tcp_server_add_all_local_addrs(grpc_tcp_server *s,
                                                 unsigned port_index,
                                                 int requested_port,
                                                 int *out_port) {
-  return GRPC_ERROR_CREATE("no ifaddrs available");
+  return GRPC_ERROR_CREATE_FROM_STATIC_STRING("no ifaddrs available");
 }
 
 bool grpc_tcp_server_have_ifaddrs(void) { return false; }
diff --git a/src/core/lib/iomgr/tcp_server_uv.c b/src/core/lib/iomgr/tcp_server_uv.c
index eed2773f8a..e9246948f5 100644
--- a/src/core/lib/iomgr/tcp_server_uv.c
+++ b/src/core/lib/iomgr/tcp_server_uv.c
@@ -95,8 +95,8 @@ grpc_error *grpc_tcp_server_create(grpc_exec_ctx *exec_ctx,
       } else {
         grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
-        return GRPC_ERROR_CREATE(GRPC_ARG_RESOURCE_QUOTA
-                                 " must be a pointer to a buffer pool");
+        return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+            GRPC_ARG_RESOURCE_QUOTA " must be a pointer to a buffer pool");
       }
     }
   }
@@ -244,17 +244,19 @@ static grpc_error *add_socket_to_server(grpc_tcp_server *s, uv_tcp_t *handle,
   // The last argument to uv_tcp_bind is flags
   status = uv_tcp_bind(handle, (struct sockaddr *)addr->addr, 0);
   if (status != 0) {
-    error = GRPC_ERROR_CREATE("Failed to bind to port");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to bind to port");
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, uv_strerror(status));
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string(uv_strerror(status)));
     return error;
   }
 
   status = uv_listen((uv_stream_t *)handle, SOMAXCONN, on_connect);
   if (status != 0) {
-    error = GRPC_ERROR_CREATE("Failed to listen to port");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to listen to port");
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, uv_strerror(status));
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string(uv_strerror(status)));
     return error;
   }
 
@@ -262,9 +264,10 @@ static grpc_error *add_socket_to_server(grpc_tcp_server *s, uv_tcp_t *handle,
   status = uv_tcp_getsockname(handle, (struct sockaddr *)&sockname_temp.addr,
                               (int *)&sockname_temp.len);
   if (status != 0) {
-    error = GRPC_ERROR_CREATE("getsockname failed");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("getsockname failed");
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, uv_strerror(status));
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string(uv_strerror(status)));
     return error;
   }
 
@@ -346,15 +349,17 @@ grpc_error *grpc_tcp_server_add_port(grpc_tcp_server *s,
   if (status == 0) {
     error = add_socket_to_server(s, handle, addr, port_index, &sp);
   } else {
-    error = GRPC_ERROR_CREATE("Failed to initialize UV tcp handle");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Failed to initialize UV tcp handle");
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, uv_strerror(status));
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string(uv_strerror(status)));
   }
 
   gpr_free(allocated_addr);
 
   if (error != GRPC_ERROR_NONE) {
-    grpc_error *error_out = GRPC_ERROR_CREATE_REFERENCING(
+    grpc_error *error_out = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
         "Failed to add port to server", &error, 1);
     GRPC_ERROR_UNREF(error);
     error = error_out;
diff --git a/src/core/lib/iomgr/tcp_server_windows.c b/src/core/lib/iomgr/tcp_server_windows.c
index bd4b9b2df1..12ce7d3fdd 100644
--- a/src/core/lib/iomgr/tcp_server_windows.c
+++ b/src/core/lib/iomgr/tcp_server_windows.c
@@ -122,8 +122,8 @@ grpc_error *grpc_tcp_server_create(grpc_exec_ctx *exec_ctx,
       } else {
         grpc_resource_quota_unref_internal(exec_ctx, s->resource_quota);
         gpr_free(s);
-        return GRPC_ERROR_CREATE(GRPC_ARG_RESOURCE_QUOTA
-                                 " must be a pointer to a buffer pool");
+        return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+            GRPC_ARG_RESOURCE_QUOTA " must be a pointer to a buffer pool");
       }
     }
   }
@@ -248,9 +248,10 @@ failure:
   GPR_ASSERT(error != GRPC_ERROR_NONE);
   char *tgtaddr = grpc_sockaddr_to_uri(addr);
   grpc_error_set_int(
-      grpc_error_set_str(GRPC_ERROR_CREATE_REFERENCING(
+      grpc_error_set_str(GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                              "Failed to prepare server socket", &error, 1),
-                         GRPC_ERROR_STR_TARGET_ADDRESS, tgtaddr),
+                         GRPC_ERROR_STR_TARGET_ADDRESS,
+                         grpc_slice_from_copied_string(tgtaddr)),
       GRPC_ERROR_INT_FD, (intptr_t)sock);
   gpr_free(tgtaddr);
   GRPC_ERROR_UNREF(error);
@@ -533,7 +534,7 @@ done:
   gpr_free(allocated_addr);
 
   if (error != GRPC_ERROR_NONE) {
-    grpc_error *error_out = GRPC_ERROR_CREATE_REFERENCING(
+    grpc_error *error_out = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
         "Failed to add port to server", &error, 1);
     GRPC_ERROR_UNREF(error);
     error = error_out;
diff --git a/src/core/lib/iomgr/tcp_uv.c b/src/core/lib/iomgr/tcp_uv.c
index 5541c62068..8e8db9f7b4 100644
--- a/src/core/lib/iomgr/tcp_uv.c
+++ b/src/core/lib/iomgr/tcp_uv.c
@@ -152,7 +152,7 @@ static void read_callback(uv_stream_t *stream, ssize_t nread,
   // TODO(murgatroid99): figure out what the return value here means
   uv_read_stop(stream);
   if (nread == UV_EOF) {
-    error = GRPC_ERROR_CREATE("EOF");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("EOF");
   } else if (nread > 0) {
     // Successful read
     sub = grpc_slice_sub_no_ref(tcp->read_slice, 0, (size_t)nread);
@@ -173,7 +173,7 @@ static void read_callback(uv_stream_t *stream, ssize_t nread,
     }
   } else {
     // nread < 0: Error
-    error = GRPC_ERROR_CREATE("TCP Read failed");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("TCP Read failed");
   }
   grpc_closure_sched(&exec_ctx, cb, error);
   grpc_exec_ctx_finish(&exec_ctx);
@@ -193,9 +193,10 @@ static void uv_endpoint_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   status =
       uv_read_start((uv_stream_t *)tcp->handle, alloc_uv_buf, read_callback);
   if (status != 0) {
-    error = GRPC_ERROR_CREATE("TCP Read failed at start");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("TCP Read failed at start");
     error =
-        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR, uv_strerror(status));
+        grpc_error_set_str(error, GRPC_ERROR_STR_OS_ERROR,
+                           grpc_slice_from_static_string(uv_strerror(status)));
     grpc_closure_sched(exec_ctx, cb, error);
   }
   if (grpc_tcp_trace) {
@@ -214,7 +215,7 @@ static void write_callback(uv_write_t *req, int status) {
   if (status == 0) {
     error = GRPC_ERROR_NONE;
   } else {
-    error = GRPC_ERROR_CREATE("TCP Write failed");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("TCP Write failed");
   }
   if (grpc_tcp_trace) {
     const char *str = grpc_error_string(error);
@@ -249,8 +250,8 @@ static void uv_endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   }
 
   if (tcp->shutting_down) {
-    grpc_closure_sched(exec_ctx, cb,
-                       GRPC_ERROR_CREATE("TCP socket is shutting down"));
+    grpc_closure_sched(exec_ctx, cb, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                         "TCP socket is shutting down"));
     return;
   }
 
diff --git a/src/core/lib/iomgr/tcp_windows.c b/src/core/lib/iomgr/tcp_windows.c
index 6c413971e3..9134883226 100644
--- a/src/core/lib/iomgr/tcp_windows.c
+++ b/src/core/lib/iomgr/tcp_windows.c
@@ -175,7 +175,7 @@ static void on_read(grpc_exec_ctx *exec_ctx, void *tcpp, grpc_error *error) {
   if (error == GRPC_ERROR_NONE) {
     if (info->wsa_error != 0 && !tcp->shutting_down) {
       char *utf8_message = gpr_format_message(info->wsa_error);
-      error = GRPC_ERROR_CREATE(utf8_message);
+      error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(utf8_message);
       gpr_free(utf8_message);
       grpc_slice_unref_internal(exec_ctx, tcp->read_slice);
     } else {
@@ -185,9 +185,9 @@ static void on_read(grpc_exec_ctx *exec_ctx, void *tcpp, grpc_error *error) {
       } else {
         grpc_slice_unref_internal(exec_ctx, tcp->read_slice);
         error = tcp->shutting_down
-                    ? GRPC_ERROR_CREATE_REFERENCING("TCP stream shutting down",
-                                                    &tcp->shutdown_error, 1)
-                    : GRPC_ERROR_CREATE("End of TCP stream");
+                    ? GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                          "TCP stream shutting down", &tcp->shutdown_error, 1)
+                    : GRPC_ERROR_CREATE_FROM_STATIC_STRING("End of TCP stream");
       }
     }
   }
@@ -208,9 +208,10 @@ static void win_read(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   WSABUF buffer;
 
   if (tcp->shutting_down) {
-    grpc_closure_sched(exec_ctx, cb, GRPC_ERROR_CREATE_REFERENCING(
-                                         "TCP socket is shutting down",
-                                         &tcp->shutdown_error, 1));
+    grpc_closure_sched(
+        exec_ctx, cb,
+        GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+            "TCP socket is shutting down", &tcp->shutdown_error, 1));
     return;
   }
 
@@ -297,9 +298,10 @@ static void win_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *ep,
   size_t len;
 
   if (tcp->shutting_down) {
-    grpc_closure_sched(exec_ctx, cb, GRPC_ERROR_CREATE_REFERENCING(
-                                         "TCP socket is shutting down",
-                                         &tcp->shutdown_error, 1));
+    grpc_closure_sched(
+        exec_ctx, cb,
+        GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+            "TCP socket is shutting down", &tcp->shutdown_error, 1));
     return;
   }
 
diff --git a/src/core/lib/iomgr/timer_generic.c b/src/core/lib/iomgr/timer_generic.c
index d4df96c214..e53c801929 100644
--- a/src/core/lib/iomgr/timer_generic.c
+++ b/src/core/lib/iomgr/timer_generic.c
@@ -109,8 +109,9 @@ void grpc_timer_list_init(gpr_timespec now) {
 
 void grpc_timer_list_shutdown(grpc_exec_ctx *exec_ctx) {
   int i;
-  run_some_expired_timers(exec_ctx, gpr_inf_future(g_clock_type), NULL,
-                          GRPC_ERROR_CREATE("Timer list shutdown"));
+  run_some_expired_timers(
+      exec_ctx, gpr_inf_future(g_clock_type), NULL,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Timer list shutdown"));
   for (i = 0; i < NUM_SHARDS; i++) {
     shard_type *shard = &g_shards[i];
     gpr_mu_destroy(&shard->mu);
@@ -182,9 +183,9 @@ void grpc_timer_init(grpc_exec_ctx *exec_ctx, grpc_timer *timer,
 
   if (!g_initialized) {
     timer->pending = false;
-    grpc_closure_sched(
-        exec_ctx, timer->closure,
-        GRPC_ERROR_CREATE("Attempt to create timer before initialization"));
+    grpc_closure_sched(exec_ctx, timer->closure,
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                           "Attempt to create timer before initialization"));
     return;
   }
 
@@ -376,7 +377,7 @@ bool grpc_timer_check(grpc_exec_ctx *exec_ctx, gpr_timespec now,
       exec_ctx, now, next,
       gpr_time_cmp(now, gpr_inf_future(now.clock_type)) != 0
           ? GRPC_ERROR_NONE
-          : GRPC_ERROR_CREATE("Shutting down timer system"));
+          : GRPC_ERROR_CREATE_FROM_STATIC_STRING("Shutting down timer system"));
 }
 
 #endif /* GRPC_TIMER_USE_GENERIC */
diff --git a/src/core/lib/iomgr/udp_server.c b/src/core/lib/iomgr/udp_server.c
index 71e295770a..28f2bd9359 100644
--- a/src/core/lib/iomgr/udp_server.c
+++ b/src/core/lib/iomgr/udp_server.c
@@ -205,8 +205,8 @@ void grpc_udp_server_destroy(grpc_exec_ctx *exec_ctx, grpc_udp_server *s,
     for (sp = s->head; sp; sp = sp->next) {
       GPR_ASSERT(sp->orphan_cb);
       sp->orphan_cb(exec_ctx, sp->emfd, sp->server->user_data);
-      grpc_fd_shutdown(exec_ctx, sp->emfd,
-                       GRPC_ERROR_CREATE("Server destroyed"));
+      grpc_fd_shutdown(exec_ctx, sp->emfd, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                               "Server destroyed"));
     }
     gpr_mu_unlock(&s->mu);
   } else {
diff --git a/src/core/lib/iomgr/unix_sockets_posix.c b/src/core/lib/iomgr/unix_sockets_posix.c
index 1233cec04e..281865aece 100644
--- a/src/core/lib/iomgr/unix_sockets_posix.c
+++ b/src/core/lib/iomgr/unix_sockets_posix.c
@@ -60,7 +60,7 @@ grpc_error *grpc_resolve_unix_domain_address(const char *name,
     gpr_asprintf(&err_msg,
                  "Path name should not have more than %" PRIuPTR " characters.",
                  GPR_ARRAY_SIZE(un->sun_path) - 1);
-    err = GRPC_ERROR_CREATE(err_msg);
+    err = GRPC_ERROR_CREATE_FROM_COPIED_STRING(err_msg);
     gpr_free(err_msg);
     return err;
   }
diff --git a/src/core/lib/iomgr/unix_sockets_posix_noop.c b/src/core/lib/iomgr/unix_sockets_posix_noop.c
index 1daf5152c1..b9602cbf8b 100644
--- a/src/core/lib/iomgr/unix_sockets_posix_noop.c
+++ b/src/core/lib/iomgr/unix_sockets_posix_noop.c
@@ -47,7 +47,8 @@ void grpc_create_socketpair_if_unix(int sv[2]) {
 grpc_error *grpc_resolve_unix_domain_address(
     const char *name, grpc_resolved_addresses **addresses) {
   *addresses = NULL;
-  return GRPC_ERROR_CREATE("Unix domain sockets are not supported on Windows");
+  return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+      "Unix domain sockets are not supported on Windows");
 }
 
 int grpc_is_unix_socket(const grpc_resolved_address *addr) { return false; }
diff --git a/src/core/lib/profiling/basic_timers.c b/src/core/lib/profiling/basic_timers.c
index 1f1987fb8e..bc8e27714c 100644
--- a/src/core/lib/profiling/basic_timers.c
+++ b/src/core/lib/profiling/basic_timers.c
@@ -218,7 +218,7 @@ void gpr_timers_set_log_filename(const char *filename) {
 static void init_output() {
   gpr_thd_options options = gpr_thd_options_default();
   gpr_thd_options_set_joinable(&options);
-  gpr_thd_new(&g_writing_thread, writing_thread, NULL, &options);
+  GPR_ASSERT(gpr_thd_new(&g_writing_thread, writing_thread, NULL, &options));
   atexit(finish_writing);
 }
 
diff --git a/src/core/lib/security/credentials/google_default/google_default_credentials.c b/src/core/lib/security/credentials/google_default/google_default_credentials.c
index dd44621347..97501e6788 100644
--- a/src/core/lib/security/credentials/google_default/google_default_credentials.c
+++ b/src/core/lib/security/credentials/google_default/google_default_credentials.c
@@ -180,7 +180,7 @@ static grpc_error *create_default_creds_from_path(
   grpc_slice creds_data = grpc_empty_slice();
   grpc_error *error = GRPC_ERROR_NONE;
   if (creds_path == NULL) {
-    error = GRPC_ERROR_CREATE("creds_path unset");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("creds_path unset");
     goto end;
   }
   error = grpc_load_file(creds_path, 0, &creds_data);
@@ -190,10 +190,9 @@ static grpc_error *create_default_creds_from_path(
   json = grpc_json_parse_string_with_len(
       (char *)GRPC_SLICE_START_PTR(creds_data), GRPC_SLICE_LENGTH(creds_data));
   if (json == NULL) {
-    char *dump = grpc_dump_slice(creds_data, GPR_DUMP_HEX | GPR_DUMP_ASCII);
-    error = grpc_error_set_str(GRPC_ERROR_CREATE("Failed to parse JSON"),
-                               GRPC_ERROR_STR_RAW_BYTES, dump);
-    gpr_free(dump);
+    error = grpc_error_set_str(
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Failed to parse JSON"),
+        GRPC_ERROR_STR_RAW_BYTES, grpc_slice_ref_internal(creds_data));
     goto end;
   }
 
@@ -204,7 +203,7 @@ static grpc_error *create_default_creds_from_path(
         grpc_service_account_jwt_access_credentials_create_from_auth_json_key(
             exec_ctx, key, grpc_max_auth_token_lifetime());
     if (result == NULL) {
-      error = GRPC_ERROR_CREATE(
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
           "grpc_service_account_jwt_access_credentials_create_from_auth_json_"
           "key failed");
     }
@@ -217,7 +216,7 @@ static grpc_error *create_default_creds_from_path(
     result =
         grpc_refresh_token_credentials_create_from_auth_refresh_token(token);
     if (result == NULL) {
-      error = GRPC_ERROR_CREATE(
+      error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
           "grpc_refresh_token_credentials_create_from_auth_refresh_token "
           "failed");
     }
@@ -236,7 +235,8 @@ end:
 grpc_channel_credentials *grpc_google_default_credentials_create(void) {
   grpc_channel_credentials *result = NULL;
   grpc_call_credentials *call_creds = NULL;
-  grpc_error *error = GRPC_ERROR_CREATE("Failed to create Google credentials");
+  grpc_error *error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+      "Failed to create Google credentials");
   grpc_error *err;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
 
@@ -274,7 +274,8 @@ grpc_channel_credentials *grpc_google_default_credentials_create(void) {
       call_creds = grpc_google_compute_engine_credentials_create(NULL);
       if (call_creds == NULL) {
         error = grpc_error_add_child(
-            error, GRPC_ERROR_CREATE("Failed to get credentials from network"));
+            error, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                       "Failed to get credentials from network"));
       }
     }
   }
diff --git a/src/core/lib/security/transport/client_auth_filter.c b/src/core/lib/security/transport/client_auth_filter.c
index 8dea1d98ff..8f321b9911 100644
--- a/src/core/lib/security/transport/client_auth_filter.c
+++ b/src/core/lib/security/transport/client_auth_filter.c
@@ -95,7 +95,8 @@ static void reset_auth_metadata_context(
 static void add_error(grpc_error **combined, grpc_error *error) {
   if (error == GRPC_ERROR_NONE) return;
   if (*combined == GRPC_ERROR_NONE) {
-    *combined = GRPC_ERROR_CREATE("Client auth metadata plugin error");
+    *combined = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Client auth metadata plugin error");
   }
   *combined = grpc_error_add_child(*combined, error);
 }
@@ -114,9 +115,10 @@ static void on_credentials_metadata(grpc_exec_ctx *exec_ctx, void *user_data,
   grpc_error *error = GRPC_ERROR_NONE;
   if (status != GRPC_CREDENTIALS_OK) {
     error = grpc_error_set_int(
-        GRPC_ERROR_CREATE(error_details != NULL && strlen(error_details) > 0
-                              ? error_details
-                              : "Credentials failed to get metadata."),
+        GRPC_ERROR_CREATE_FROM_COPIED_STRING(
+            error_details != NULL && strlen(error_details) > 0
+                ? error_details
+                : "Credentials failed to get metadata."),
         GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAUTHENTICATED);
   } else {
     GPR_ASSERT(num_md <= MAX_CREDENTIALS_METADATA_COUNT);
@@ -192,7 +194,7 @@ static void send_security_metadata(grpc_exec_ctx *exec_ctx,
       grpc_transport_stream_op_finish_with_failure(
           exec_ctx, op,
           grpc_error_set_int(
-              GRPC_ERROR_CREATE(
+              GRPC_ERROR_CREATE_FROM_STATIC_STRING(
                   "Incompatible credentials set on channel and call."),
               GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_UNAUTHENTICATED));
       return;
@@ -225,9 +227,10 @@ static void on_host_checked(grpc_exec_ctx *exec_ctx, void *user_data,
                  host);
     gpr_free(host);
     grpc_call_element_signal_error(
-        exec_ctx, elem, grpc_error_set_int(GRPC_ERROR_CREATE(error_msg),
-                                           GRPC_ERROR_INT_GRPC_STATUS,
-                                           GRPC_STATUS_UNAUTHENTICATED));
+        exec_ctx, elem,
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_msg),
+                           GRPC_ERROR_INT_GRPC_STATUS,
+                           GRPC_STATUS_UNAUTHENTICATED));
     gpr_free(error_msg);
   }
 }
diff --git a/src/core/lib/security/transport/secure_endpoint.c b/src/core/lib/security/transport/secure_endpoint.c
index 7d58843d69..568d70fa38 100644
--- a/src/core/lib/security/transport/secure_endpoint.c
+++ b/src/core/lib/security/transport/secure_endpoint.c
@@ -162,7 +162,7 @@ static void on_read(grpc_exec_ctx *exec_ctx, void *user_data,
 
   if (error != GRPC_ERROR_NONE) {
     grpc_slice_buffer_reset_and_unref_internal(exec_ctx, ep->read_buffer);
-    call_read_cb(exec_ctx, ep, GRPC_ERROR_CREATE_REFERENCING(
+    call_read_cb(exec_ctx, ep, GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
                                    "Secure read failed", &error, 1));
     return;
   }
@@ -220,8 +220,10 @@ static void on_read(grpc_exec_ctx *exec_ctx, void *user_data,
 
   if (result != TSI_OK) {
     grpc_slice_buffer_reset_and_unref_internal(exec_ctx, ep->read_buffer);
-    call_read_cb(exec_ctx, ep, grpc_set_tsi_error_result(
-                                   GRPC_ERROR_CREATE("Unwrap failed"), result));
+    call_read_cb(
+        exec_ctx, ep,
+        grpc_set_tsi_error_result(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Unwrap failed"), result));
     return;
   }
 
@@ -332,7 +334,8 @@ static void endpoint_write(grpc_exec_ctx *exec_ctx, grpc_endpoint *secure_ep,
     grpc_slice_buffer_reset_and_unref_internal(exec_ctx, &ep->output_buffer);
     grpc_closure_sched(
         exec_ctx, cb,
-        grpc_set_tsi_error_result(GRPC_ERROR_CREATE("Wrap failed"), result));
+        grpc_set_tsi_error_result(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Wrap failed"), result));
     GPR_TIMER_END("secure_endpoint.endpoint_write", 0);
     return;
   }
diff --git a/src/core/lib/security/transport/security_connector.c b/src/core/lib/security/transport/security_connector.c
index ad083a730f..b0cbc83639 100644
--- a/src/core/lib/security/transport/security_connector.c
+++ b/src/core/lib/security/transport/security_connector.c
@@ -137,9 +137,9 @@ void grpc_security_connector_check_peer(grpc_exec_ctx *exec_ctx,
                                         grpc_auth_context **auth_context,
                                         grpc_closure *on_peer_checked) {
   if (sc == NULL) {
-    grpc_closure_sched(
-        exec_ctx, on_peer_checked,
-        GRPC_ERROR_CREATE("cannot check peer -- no security connector"));
+    grpc_closure_sched(exec_ctx, on_peer_checked,
+                       GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                           "cannot check peer -- no security connector"));
     tsi_peer_destruct(&peer);
   } else {
     sc->vtable->check_peer(exec_ctx, sc, peer, auth_context, on_peer_checked);
@@ -330,7 +330,8 @@ static void fake_check_peer(grpc_exec_ctx *exec_ctx,
   grpc_error *error = GRPC_ERROR_NONE;
   *auth_context = NULL;
   if (peer.property_count != 1) {
-    error = GRPC_ERROR_CREATE("Fake peers should only have 1 property.");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Fake peers should only have 1 property.");
     goto end;
   }
   prop_name = peer.properties[0].name;
@@ -339,13 +340,14 @@ static void fake_check_peer(grpc_exec_ctx *exec_ctx,
     char *msg;
     gpr_asprintf(&msg, "Unexpected property in fake peer: %s.",
                  prop_name == NULL ? "<EMPTY>" : prop_name);
-    error = GRPC_ERROR_CREATE(msg);
+    error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     goto end;
   }
   if (strncmp(peer.properties[0].value.data, TSI_FAKE_CERTIFICATE_TYPE,
               peer.properties[0].value.length)) {
-    error = GRPC_ERROR_CREATE("Invalid value for cert type property.");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Invalid value for cert type property.");
     goto end;
   }
   *auth_context = grpc_auth_context_create(NULL);
@@ -586,18 +588,19 @@ static grpc_error *ssl_check_peer(grpc_security_connector *sc,
   const tsi_peer_property *p =
       tsi_peer_get_property_by_name(peer, TSI_SSL_ALPN_SELECTED_PROTOCOL);
   if (p == NULL) {
-    return GRPC_ERROR_CREATE(
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
         "Cannot check peer: missing selected ALPN property.");
   }
   if (!grpc_chttp2_is_alpn_version_supported(p->value.data, p->value.length)) {
-    return GRPC_ERROR_CREATE("Cannot check peer: invalid ALPN value.");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Cannot check peer: invalid ALPN value.");
   }
 
   /* Check the peer name if specified. */
   if (peer_name != NULL && !ssl_host_matches_name(peer, peer_name)) {
     char *msg;
     gpr_asprintf(&msg, "Peer name %s is not in peer certificate", peer_name);
-    grpc_error *error = GRPC_ERROR_CREATE(msg);
+    grpc_error *error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(msg);
     gpr_free(msg);
     return error;
   }
diff --git a/src/core/lib/security/transport/security_handshaker.c b/src/core/lib/security/transport/security_handshaker.c
index 7065d261ba..2f39327670 100644
--- a/src/core/lib/security/transport/security_handshaker.c
+++ b/src/core/lib/security/transport/security_handshaker.c
@@ -120,7 +120,7 @@ static void security_handshake_failed_locked(grpc_exec_ctx *exec_ctx,
   if (error == GRPC_ERROR_NONE) {
     // If we were shut down after the handshake succeeded but before an
     // endpoint callback was invoked, we need to generate our own error.
-    error = GRPC_ERROR_CREATE("Handshaker shutdown");
+    error = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshaker shutdown");
   }
   const char *msg = grpc_error_string(error);
   gpr_log(GPR_DEBUG, "Security handshake failed: %s", msg);
@@ -156,7 +156,8 @@ static void on_peer_checked(grpc_exec_ctx *exec_ctx, void *arg,
       tsi_handshaker_create_frame_protector(h->handshaker, NULL, &protector);
   if (result != TSI_OK) {
     error = grpc_set_tsi_error_result(
-        GRPC_ERROR_CREATE("Frame protector creation failed"), result);
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Frame protector creation failed"),
+        result);
     security_handshake_failed_locked(exec_ctx, h, error);
     goto done;
   }
@@ -191,7 +192,7 @@ static grpc_error *check_peer_locked(grpc_exec_ctx *exec_ctx,
   tsi_result result = tsi_handshaker_extract_peer(h->handshaker, &peer);
   if (result != TSI_OK) {
     return grpc_set_tsi_error_result(
-        GRPC_ERROR_CREATE("Peer extraction failed"), result);
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Peer extraction failed"), result);
   }
   grpc_security_connector_check_peer(exec_ctx, h->connector, peer,
                                      &h->auth_context, &h->on_peer_checked);
@@ -215,8 +216,8 @@ static grpc_error *send_handshake_bytes_to_peer_locked(grpc_exec_ctx *exec_ctx,
     }
   } while (result == TSI_INCOMPLETE_DATA);
   if (result != TSI_OK) {
-    return grpc_set_tsi_error_result(GRPC_ERROR_CREATE("Handshake failed"),
-                                     result);
+    return grpc_set_tsi_error_result(
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshake failed"), result);
   }
   // Send data.
   grpc_slice to_send =
@@ -234,8 +235,8 @@ static void on_handshake_data_received_from_peer(grpc_exec_ctx *exec_ctx,
   gpr_mu_lock(&h->mu);
   if (error != GRPC_ERROR_NONE || h->shutdown) {
     security_handshake_failed_locked(
-        exec_ctx, h,
-        GRPC_ERROR_CREATE_REFERENCING("Handshake read failed", &error, 1));
+        exec_ctx, h, GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                         "Handshake read failed", &error, 1));
     gpr_mu_unlock(&h->mu);
     security_handshaker_unref(exec_ctx, h);
     return;
@@ -270,8 +271,9 @@ static void on_handshake_data_received_from_peer(grpc_exec_ctx *exec_ctx,
   }
   if (result != TSI_OK) {
     security_handshake_failed_locked(
-        exec_ctx, h, grpc_set_tsi_error_result(
-                         GRPC_ERROR_CREATE("Handshake failed"), result));
+        exec_ctx, h,
+        grpc_set_tsi_error_result(
+            GRPC_ERROR_CREATE_FROM_STATIC_STRING("Handshake failed"), result));
     gpr_mu_unlock(&h->mu);
     security_handshaker_unref(exec_ctx, h);
     return;
@@ -314,8 +316,8 @@ static void on_handshake_data_sent_to_peer(grpc_exec_ctx *exec_ctx, void *arg,
   gpr_mu_lock(&h->mu);
   if (error != GRPC_ERROR_NONE || h->shutdown) {
     security_handshake_failed_locked(
-        exec_ctx, h,
-        GRPC_ERROR_CREATE_REFERENCING("Handshake write failed", &error, 1));
+        exec_ctx, h, GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+                         "Handshake write failed", &error, 1));
     gpr_mu_unlock(&h->mu);
     security_handshaker_unref(exec_ctx, h);
     return;
@@ -429,7 +431,8 @@ static void fail_handshaker_do_handshake(grpc_exec_ctx *exec_ctx,
                                          grpc_closure *on_handshake_done,
                                          grpc_handshaker_args *args) {
   grpc_closure_sched(exec_ctx, on_handshake_done,
-                     GRPC_ERROR_CREATE("Failed to create security handshaker"));
+                     GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                         "Failed to create security handshaker"));
 }
 
 static const grpc_handshaker_vtable fail_handshaker_vtable = {
diff --git a/src/core/lib/security/transport/server_auth_filter.c b/src/core/lib/security/transport/server_auth_filter.c
index 01cb473177..3cf0632220 100644
--- a/src/core/lib/security/transport/server_auth_filter.c
+++ b/src/core/lib/security/transport/server_auth_filter.c
@@ -144,9 +144,10 @@ static void on_md_processing_done(
       calld->transport_op->send_message = NULL;
     }
     calld->transport_op->send_trailing_metadata = NULL;
-    grpc_closure_sched(&exec_ctx, calld->on_done_recv,
-                       grpc_error_set_int(GRPC_ERROR_CREATE(error_details),
-                                          GRPC_ERROR_INT_GRPC_STATUS, status));
+    grpc_closure_sched(
+        &exec_ctx, calld->on_done_recv,
+        grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(error_details),
+                           GRPC_ERROR_INT_GRPC_STATUS, status));
   }
 
   grpc_exec_ctx_finish(&exec_ctx);
@@ -158,7 +159,7 @@ static void auth_on_recv(grpc_exec_ctx *exec_ctx, void *user_data,
   call_data *calld = elem->call_data;
   channel_data *chand = elem->channel_data;
   if (error == GRPC_ERROR_NONE) {
-    if (chand->creds->processor.process != NULL) {
+    if (chand->creds != NULL && chand->creds->processor.process != NULL) {
       calld->md = metadata_batch_to_md_array(calld->recv_initial_metadata);
       chand->creds->processor.process(
           chand->creds->processor.state, calld->auth_context,
@@ -242,7 +243,6 @@ static grpc_error *init_channel_elem(grpc_exec_ctx *exec_ctx,
 
   GPR_ASSERT(!args->is_last);
   GPR_ASSERT(auth_context != NULL);
-  GPR_ASSERT(creds != NULL);
 
   /* initialize members */
   chand->auth_context =
diff --git a/src/core/lib/security/transport/tsi_error.c b/src/core/lib/security/transport/tsi_error.c
index afc1733567..eae0a676b0 100644
--- a/src/core/lib/security/transport/tsi_error.c
+++ b/src/core/lib/security/transport/tsi_error.c
@@ -34,7 +34,9 @@
 #include "src/core/lib/security/transport/tsi_error.h"
 
 grpc_error *grpc_set_tsi_error_result(grpc_error *error, tsi_result result) {
-  return grpc_error_set_int(grpc_error_set_str(error, GRPC_ERROR_STR_TSI_ERROR,
-                                               tsi_result_to_string(result)),
-                            GRPC_ERROR_INT_TSI_CODE, result);
+  return grpc_error_set_int(
+      grpc_error_set_str(
+          error, GRPC_ERROR_STR_TSI_ERROR,
+          grpc_slice_from_static_string(tsi_result_to_string(result))),
+      GRPC_ERROR_INT_TSI_CODE, result);
 }
diff --git a/src/core/ext/client_channel/default_initial_connect_string.c b/src/core/lib/support/atm.c
index 6db82d84ef..06e8432caf 100644
--- a/src/core/ext/client_channel/default_initial_connect_string.c
+++ b/src/core/lib/support/atm.c
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2017, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -31,8 +31,17 @@
  *
  */
 
-#include <grpc/slice.h>
-#include "src/core/lib/iomgr/resolve_address.h"
+#include <grpc/support/atm.h>
+#include <grpc/support/useful.h>
 
-void grpc_set_default_initial_connect_string(grpc_resolved_address **addr,
-                                             grpc_slice *initial_str) {}
+gpr_atm gpr_atm_no_barrier_clamped_add(gpr_atm *value, gpr_atm delta,
+                                       gpr_atm min, gpr_atm max) {
+  gpr_atm current;
+  gpr_atm new;
+  do {
+    current = gpr_atm_no_barrier_load(value);
+    new = GPR_CLAMP(current + delta, min, max);
+    if (new == current) break;
+  } while (!gpr_atm_no_barrier_cas(value, current, new));
+  return new;
+}
diff --git a/src/core/lib/surface/call.c b/src/core/lib/surface/call.c
index 2c5d8c0ff3..895a8a3b06 100644
--- a/src/core/lib/surface/call.c
+++ b/src/core/lib/surface/call.c
@@ -264,7 +264,7 @@ static void add_batch_error(grpc_exec_ctx *exec_ctx, batch_control *bctl,
 static void add_init_error(grpc_error **composite, grpc_error *new) {
   if (new == GRPC_ERROR_NONE) return;
   if (*composite == GRPC_ERROR_NONE)
-    *composite = GRPC_ERROR_CREATE("Call creation failed");
+    *composite = GRPC_ERROR_CREATE_FROM_STATIC_STRING("Call creation failed");
   *composite = grpc_error_add_child(*composite, new);
 }
 
@@ -335,17 +335,17 @@ grpc_error *grpc_call_create(grpc_exec_ctx *exec_ctx,
      * call. */
     if (args->propagation_mask & GRPC_PROPAGATE_CENSUS_TRACING_CONTEXT) {
       if (0 == (args->propagation_mask & GRPC_PROPAGATE_CENSUS_STATS_CONTEXT)) {
-        add_init_error(&error,
-                       GRPC_ERROR_CREATE("Census tracing propagation requested "
-                                         "without Census context propagation"));
+        add_init_error(&error, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                   "Census tracing propagation requested "
+                                   "without Census context propagation"));
       }
       grpc_call_context_set(
           call, GRPC_CONTEXT_TRACING,
           args->parent_call->context[GRPC_CONTEXT_TRACING].value, NULL);
     } else if (args->propagation_mask & GRPC_PROPAGATE_CENSUS_STATS_CONTEXT) {
-      add_init_error(&error,
-                     GRPC_ERROR_CREATE("Census context propagation requested "
-                                       "without Census tracing propagation"));
+      add_init_error(&error, GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                 "Census context propagation requested "
+                                 "without Census tracing propagation"));
     }
     if (args->propagation_mask & GRPC_PROPAGATE_CANCELLATION) {
       call->cancellation_is_inherited = 1;
@@ -603,8 +603,9 @@ static void cancel_with_error(grpc_exec_ctx *exec_ctx, grpc_call *c,
 static grpc_error *error_from_status(grpc_status_code status,
                                      const char *description) {
   return grpc_error_set_int(
-      grpc_error_set_str(GRPC_ERROR_CREATE(description),
-                         GRPC_ERROR_STR_GRPC_MESSAGE, description),
+      grpc_error_set_str(GRPC_ERROR_CREATE_FROM_COPIED_STRING(description),
+                         GRPC_ERROR_STR_GRPC_MESSAGE,
+                         grpc_slice_from_copied_string(description)),
       GRPC_ERROR_INT_GRPC_STATUS, status);
 }
 
@@ -624,16 +625,15 @@ static bool get_final_status_from(
     void (*set_value)(grpc_status_code code, void *user_data),
     void *set_value_user_data, grpc_slice *details) {
   grpc_status_code code;
-  const char *msg = NULL;
-  grpc_error_get_status(error, call->send_deadline, &code, &msg, NULL);
+  grpc_slice slice;
+  grpc_error_get_status(error, call->send_deadline, &code, &slice, NULL);
   if (code == GRPC_STATUS_OK && !allow_ok_status) {
     return false;
   }
 
   set_value(code, set_value_user_data);
   if (details != NULL) {
-    *details =
-        msg == NULL ? grpc_empty_slice() : grpc_slice_from_copied_string(msg);
+    *details = grpc_slice_ref_internal(slice);
   }
   return true;
 }
@@ -896,18 +896,19 @@ static void recv_common_filter(grpc_exec_ctx *exec_ctx, grpc_call *call,
     grpc_error *error =
         status_code == GRPC_STATUS_OK
             ? GRPC_ERROR_NONE
-            : grpc_error_set_int(GRPC_ERROR_CREATE("Error received from peer"),
+            : grpc_error_set_int(GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                                     "Error received from peer"),
                                  GRPC_ERROR_INT_GRPC_STATUS,
                                  (intptr_t)status_code);
 
     if (b->idx.named.grpc_message != NULL) {
-      char *msg =
-          grpc_slice_to_c_string(GRPC_MDVALUE(b->idx.named.grpc_message->md));
-      error = grpc_error_set_str(error, GRPC_ERROR_STR_GRPC_MESSAGE, msg);
-      gpr_free(msg);
+      error = grpc_error_set_str(
+          error, GRPC_ERROR_STR_GRPC_MESSAGE,
+          grpc_slice_ref_internal(GRPC_MDVALUE(b->idx.named.grpc_message->md)));
       grpc_metadata_batch_remove(exec_ctx, b, b->idx.named.grpc_message);
     } else if (error != GRPC_ERROR_NONE) {
-      error = grpc_error_set_str(error, GRPC_ERROR_STR_GRPC_MESSAGE, "");
+      error = grpc_error_set_str(error, GRPC_ERROR_STR_GRPC_MESSAGE,
+                                 grpc_empty_slice());
     }
 
     set_status_from_error(exec_ctx, call, STATUS_FROM_WIRE, error);
@@ -1056,8 +1057,8 @@ static grpc_error *consolidate_batch_errors(batch_control *bctl) {
     bctl->errors[0] = NULL;
     return e;
   } else {
-    grpc_error *error =
-        GRPC_ERROR_CREATE_REFERENCING("Call batch failed", bctl->errors, n);
+    grpc_error *error = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+        "Call batch failed", bctl->errors, n);
     for (size_t i = 0; i < n; i++) {
       GRPC_ERROR_UNREF(bctl->errors[i]);
       bctl->errors[i] = NULL;
@@ -1521,7 +1522,8 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
         {
           grpc_error *override_error = GRPC_ERROR_NONE;
           if (op->data.send_status_from_server.status != GRPC_STATUS_OK) {
-            override_error = GRPC_ERROR_CREATE("Error from server send status");
+            override_error = GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+                "Error from server send status");
           }
           if (op->data.send_status_from_server.status_details != NULL) {
             call->send_extra_metadata[1].md = grpc_mdelem_from_slices(
@@ -1531,8 +1533,9 @@ static grpc_call_error call_start_batch(grpc_exec_ctx *exec_ctx,
             call->send_extra_metadata_count++;
             char *msg = grpc_slice_to_c_string(
                 GRPC_MDVALUE(call->send_extra_metadata[1].md));
-            override_error = grpc_error_set_str(
-                override_error, GRPC_ERROR_STR_GRPC_MESSAGE, msg);
+            override_error =
+                grpc_error_set_str(override_error, GRPC_ERROR_STR_GRPC_MESSAGE,
+                                   grpc_slice_from_copied_string(msg));
             gpr_free(msg);
           }
           set_status_from_error(exec_ctx, call, STATUS_FROM_API_OVERRIDE,
diff --git a/src/core/lib/surface/channel.c b/src/core/lib/surface/channel.c
index 2b700b2f67..d6c7aee40d 100644
--- a/src/core/lib/surface/channel.c
+++ b/src/core/lib/surface/channel.c
@@ -85,19 +85,10 @@ struct grpc_channel {
 static void destroy_channel(grpc_exec_ctx *exec_ctx, void *arg,
                             grpc_error *error);
 
-grpc_channel *grpc_channel_create(grpc_exec_ctx *exec_ctx, const char *target,
-                                  const grpc_channel_args *input_args,
-                                  grpc_channel_stack_type channel_stack_type,
-                                  grpc_transport *optional_transport) {
-  grpc_channel_stack_builder *builder = grpc_channel_stack_builder_create();
-  grpc_channel_stack_builder_set_channel_arguments(exec_ctx, builder,
-                                                   input_args);
-  grpc_channel_stack_builder_set_target(builder, target);
-  grpc_channel_stack_builder_set_transport(builder, optional_transport);
-  if (!grpc_channel_init_create_stack(exec_ctx, builder, channel_stack_type)) {
-    grpc_channel_stack_builder_destroy(exec_ctx, builder);
-    return NULL;
-  }
+grpc_channel *grpc_channel_create_with_builder(
+    grpc_exec_ctx *exec_ctx, grpc_channel_stack_builder *builder,
+    grpc_channel_stack_type channel_stack_type) {
+  char *target = gpr_strdup(grpc_channel_stack_builder_get_target(builder));
   grpc_channel_args *args = grpc_channel_args_copy(
       grpc_channel_stack_builder_get_channel_arguments(builder));
   grpc_channel *channel;
@@ -108,11 +99,12 @@ grpc_channel *grpc_channel_create(grpc_exec_ctx *exec_ctx, const char *target,
     gpr_log(GPR_ERROR, "channel stack builder failed: %s",
             grpc_error_string(error));
     GRPC_ERROR_UNREF(error);
+    gpr_free(target);
     goto done;
   }
 
   memset(channel, 0, sizeof(*channel));
-  channel->target = gpr_strdup(target);
+  channel->target = target;
   channel->is_client = grpc_channel_stack_type_is_client(channel_stack_type);
   gpr_mu_init(&channel->registered_call_mu);
   channel->registered_calls = NULL;
@@ -183,6 +175,23 @@ done:
   return channel;
 }
 
+grpc_channel *grpc_channel_create(grpc_exec_ctx *exec_ctx, const char *target,
+                                  const grpc_channel_args *input_args,
+                                  grpc_channel_stack_type channel_stack_type,
+                                  grpc_transport *optional_transport) {
+  grpc_channel_stack_builder *builder = grpc_channel_stack_builder_create();
+  grpc_channel_stack_builder_set_channel_arguments(exec_ctx, builder,
+                                                   input_args);
+  grpc_channel_stack_builder_set_target(builder, target);
+  grpc_channel_stack_builder_set_transport(builder, optional_transport);
+  if (!grpc_channel_init_create_stack(exec_ctx, builder, channel_stack_type)) {
+    grpc_channel_stack_builder_destroy(exec_ctx, builder);
+    return NULL;
+  }
+  return grpc_channel_create_with_builder(exec_ctx, builder,
+                                          channel_stack_type);
+}
+
 size_t grpc_channel_get_call_size_estimate(grpc_channel *channel) {
 #define ROUND_UP_SIZE 256
   return ((size_t)gpr_atm_no_barrier_load(&channel->call_size_estimate) +
@@ -380,7 +389,8 @@ void grpc_channel_destroy(grpc_channel *channel) {
   grpc_channel_element *elem;
   grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
   GRPC_API_TRACE("grpc_channel_destroy(channel=%p)", 1, (channel));
-  op->disconnect_with_error = GRPC_ERROR_CREATE("Channel Destroyed");
+  op->disconnect_with_error =
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Channel Destroyed");
   elem = grpc_channel_stack_element(CHANNEL_STACK_FROM_CHANNEL(channel), 0);
   elem->filter->start_transport_op(&exec_ctx, elem, op);
 
diff --git a/src/core/lib/surface/channel.h b/src/core/lib/surface/channel.h
index c4aebd8b9b..0f203a3e59 100644
--- a/src/core/lib/surface/channel.h
+++ b/src/core/lib/surface/channel.h
@@ -35,6 +35,7 @@
 #define GRPC_CORE_LIB_SURFACE_CHANNEL_H
 
 #include "src/core/lib/channel/channel_stack.h"
+#include "src/core/lib/channel/channel_stack_builder.h"
 #include "src/core/lib/surface/channel_stack_type.h"
 
 grpc_channel *grpc_channel_create(grpc_exec_ctx *exec_ctx, const char *target,
@@ -42,6 +43,10 @@ grpc_channel *grpc_channel_create(grpc_exec_ctx *exec_ctx, const char *target,
                                   grpc_channel_stack_type channel_stack_type,
                                   grpc_transport *optional_transport);
 
+grpc_channel *grpc_channel_create_with_builder(
+    grpc_exec_ctx *exec_ctx, grpc_channel_stack_builder *builder,
+    grpc_channel_stack_type channel_stack_type);
+
 /** Create a call given a grpc_channel, in order to call \a method.
     Progress is tied to activity on \a pollset_set. The returned call object is
     meant to be used with \a grpc_call_start_batch_and_execute, which relies on
diff --git a/src/core/lib/surface/lame_client.c b/src/core/lib/surface/lame_client.c
index 9ddb88bd11..0c408aa288 100644
--- a/src/core/lib/surface/lame_client.c
+++ b/src/core/lib/surface/lame_client.c
@@ -90,7 +90,8 @@ static void lame_start_transport_stream_op(grpc_exec_ctx *exec_ctx,
     fill_metadata(exec_ctx, elem, op->recv_trailing_metadata);
   }
   grpc_transport_stream_op_finish_with_failure(
-      exec_ctx, op, GRPC_ERROR_CREATE("lame client channel"));
+      exec_ctx, op,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("lame client channel"));
 }
 
 static char *lame_get_peer(grpc_exec_ctx *exec_ctx, grpc_call_element *elem) {
@@ -111,8 +112,9 @@ static void lame_start_transport_op(grpc_exec_ctx *exec_ctx,
                        GRPC_ERROR_NONE);
   }
   if (op->send_ping != NULL) {
-    grpc_closure_sched(exec_ctx, op->send_ping,
-                       GRPC_ERROR_CREATE("lame client channel"));
+    grpc_closure_sched(
+        exec_ctx, op->send_ping,
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("lame client channel"));
   }
   GRPC_ERROR_UNREF(op->disconnect_with_error);
   if (op->on_consumed != NULL) {
diff --git a/src/core/lib/surface/server.c b/src/core/lib/surface/server.c
index 1186a4af63..a123c9ca43 100644
--- a/src/core/lib/surface/server.c
+++ b/src/core/lib/surface/server.c
@@ -288,10 +288,10 @@ static void send_shutdown(grpc_exec_ctx *exec_ctx, grpc_channel *channel,
   grpc_channel_element *elem;
 
   op->goaway_error =
-      send_goaway
-          ? grpc_error_set_int(GRPC_ERROR_CREATE("Server shutdown"),
-                               GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_OK)
-          : GRPC_ERROR_NONE;
+      send_goaway ? grpc_error_set_int(
+                        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Server shutdown"),
+                        GRPC_ERROR_INT_GRPC_STATUS, GRPC_STATUS_OK)
+                  : GRPC_ERROR_NONE;
   op->set_accept_stream = true;
   sc->slice = grpc_slice_from_copied_string("Server shutdown");
   op->disconnect_with_error = send_disconnect;
@@ -712,8 +712,9 @@ static void maybe_finish_shutdown(grpc_exec_ctx *exec_ctx,
     return;
   }
 
-  kill_pending_work_locked(exec_ctx, server,
-                           GRPC_ERROR_CREATE("Server Shutdown"));
+  kill_pending_work_locked(
+      exec_ctx, server,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Server Shutdown"));
 
   if (server->root_channel_data.next != &server->root_channel_data ||
       server->listeners_destroyed < num_listeners(server)) {
@@ -771,8 +772,8 @@ static void server_on_recv_initial_metadata(grpc_exec_ctx *exec_ctx, void *ptr,
     /* do nothing */
   } else {
     grpc_error *src_error = error;
-    error =
-        GRPC_ERROR_CREATE_REFERENCING("Missing :authority or :path", &error, 1);
+    error = GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
+        "Missing :authority or :path", &error, 1);
     GRPC_ERROR_UNREF(src_error);
   }
 
@@ -1219,7 +1220,8 @@ void grpc_server_setup_transport(grpc_exec_ctx *exec_ctx, grpc_server *s,
   op->on_connectivity_state_change = &chand->channel_connectivity_changed;
   op->connectivity_state = &chand->connectivity_state;
   if (gpr_atm_acq_load(&s->shutdown_flag) != 0) {
-    op->disconnect_with_error = GRPC_ERROR_CREATE("Server shutdown");
+    op->disconnect_with_error =
+        GRPC_ERROR_CREATE_FROM_STATIC_STRING("Server shutdown");
   }
   grpc_transport_perform_op(exec_ctx, transport, op);
 }
@@ -1277,8 +1279,9 @@ void grpc_server_shutdown_and_notify(grpc_server *server,
 
   /* collect all unregistered then registered calls */
   gpr_mu_lock(&server->mu_call);
-  kill_pending_work_locked(&exec_ctx, server,
-                           GRPC_ERROR_CREATE("Server Shutdown"));
+  kill_pending_work_locked(
+      &exec_ctx, server,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Server Shutdown"));
   gpr_mu_unlock(&server->mu_call);
 
   maybe_finish_shutdown(&exec_ctx, server);
@@ -1308,8 +1311,9 @@ void grpc_server_cancel_all_calls(grpc_server *server) {
   channel_broadcaster_init(server, &broadcaster);
   gpr_mu_unlock(&server->mu_global);
 
-  channel_broadcaster_shutdown(&exec_ctx, &broadcaster, false /* send_goaway */,
-                               GRPC_ERROR_CREATE("Cancelling all calls"));
+  channel_broadcaster_shutdown(
+      &exec_ctx, &broadcaster, false /* send_goaway */,
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Cancelling all calls"));
   grpc_exec_ctx_finish(&exec_ctx);
 }
 
@@ -1357,16 +1361,16 @@ static grpc_call_error queue_call_request(grpc_exec_ctx *exec_ctx,
   int request_id;
   if (gpr_atm_acq_load(&server->shutdown_flag)) {
     fail_call(exec_ctx, server, cq_idx, rc,
-              GRPC_ERROR_CREATE("Server Shutdown"));
+              GRPC_ERROR_CREATE_FROM_STATIC_STRING("Server Shutdown"));
     return GRPC_CALL_OK;
   }
   request_id = gpr_stack_lockfree_pop(server->request_freelist_per_cq[cq_idx]);
   if (request_id == -1) {
     /* out of request ids: just fail this one */
     fail_call(exec_ctx, server, cq_idx, rc,
-              grpc_error_set_int(GRPC_ERROR_CREATE("Out of request ids"),
-                                 GRPC_ERROR_INT_LIMIT,
-                                 server->max_requested_calls_per_cq));
+              grpc_error_set_int(
+                  GRPC_ERROR_CREATE_FROM_STATIC_STRING("Out of request ids"),
+                  GRPC_ERROR_INT_LIMIT, server->max_requested_calls_per_cq));
     return GRPC_CALL_OK;
   }
   switch (rc->type) {
diff --git a/src/core/lib/surface/validate_metadata.c b/src/core/lib/surface/validate_metadata.c
index 7ec9137265..6e76c4efe7 100644
--- a/src/core/lib/surface/validate_metadata.c
+++ b/src/core/lib/surface/validate_metadata.c
@@ -39,6 +39,7 @@
 #include <grpc/support/port_platform.h>
 
 #include "src/core/lib/iomgr/error.h"
+#include "src/core/lib/slice/slice_internal.h"
 #include "src/core/lib/slice/slice_string_helpers.h"
 
 static grpc_error *conforms_to(grpc_slice slice, const uint8_t *legal_bits,
@@ -52,9 +53,10 @@ static grpc_error *conforms_to(grpc_slice slice, const uint8_t *legal_bits,
     if ((legal_bits[byte] & (1 << bit)) == 0) {
       char *dump = grpc_dump_slice(slice, GPR_DUMP_HEX | GPR_DUMP_ASCII);
       grpc_error *error = grpc_error_set_str(
-          grpc_error_set_int(GRPC_ERROR_CREATE(err_desc), GRPC_ERROR_INT_OFFSET,
+          grpc_error_set_int(GRPC_ERROR_CREATE_FROM_COPIED_STRING(err_desc),
+                             GRPC_ERROR_INT_OFFSET,
                              p - GRPC_SLICE_START_PTR(slice)),
-          GRPC_ERROR_STR_RAW_BYTES, dump);
+          GRPC_ERROR_STR_RAW_BYTES, grpc_slice_from_copied_string(dump));
       gpr_free(dump);
       return error;
     }
@@ -74,10 +76,12 @@ grpc_error *grpc_validate_header_key_is_legal(grpc_slice slice) {
       0x80, 0xfe, 0xff, 0xff, 0x07, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
   if (GRPC_SLICE_LENGTH(slice) == 0) {
-    return GRPC_ERROR_CREATE("Metadata keys cannot be zero length");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Metadata keys cannot be zero length");
   }
   if (GRPC_SLICE_START_PTR(slice)[0] == ':') {
-    return GRPC_ERROR_CREATE("Metadata keys cannot start with :");
+    return GRPC_ERROR_CREATE_FROM_STATIC_STRING(
+        "Metadata keys cannot start with :");
   }
   return conforms_to(slice, legal_header_bits, "Illegal header key");
 }
diff --git a/src/core/lib/transport/connectivity_state.c b/src/core/lib/transport/connectivity_state.c
index afe1f6164d..3757b25267 100644
--- a/src/core/lib/transport/connectivity_state.c
+++ b/src/core/lib/transport/connectivity_state.c
@@ -79,7 +79,8 @@ void grpc_connectivity_state_destroy(grpc_exec_ctx *exec_ctx,
       *w->current = GRPC_CHANNEL_SHUTDOWN;
       error = GRPC_ERROR_NONE;
     } else {
-      error = GRPC_ERROR_CREATE("Shutdown connectivity owner");
+      error =
+          GRPC_ERROR_CREATE_FROM_STATIC_STRING("Shutdown connectivity owner");
     }
     grpc_closure_sched(exec_ctx, w->notify, error);
     gpr_free(w);
diff --git a/src/core/lib/transport/error_utils.c b/src/core/lib/transport/error_utils.c
index ef55e561fb..4e70f8749d 100644
--- a/src/core/lib/transport/error_utils.c
+++ b/src/core/lib/transport/error_utils.c
@@ -55,7 +55,7 @@ static grpc_error *recursively_find_error_with_field(grpc_error *error,
 }
 
 void grpc_error_get_status(grpc_error *error, gpr_timespec deadline,
-                           grpc_status_code *code, const char **msg,
+                           grpc_status_code *code, grpc_slice *slice,
                            grpc_http2_error_code *http_error) {
   // Start with the parent error and recurse through the tree of children
   // until we find the first one that has a status code.
@@ -97,11 +97,11 @@ void grpc_error_get_status(grpc_error *error, gpr_timespec deadline,
 
   // If the error has a status message, use it.  Otherwise, fall back to
   // the error description.
-  if (msg != NULL) {
-    *msg = grpc_error_get_str(found_error, GRPC_ERROR_STR_GRPC_MESSAGE);
-    if (*msg == NULL && error != GRPC_ERROR_NONE) {
-      *msg = grpc_error_get_str(found_error, GRPC_ERROR_STR_DESCRIPTION);
-      if (*msg == NULL) *msg = "unknown error";  // Just in case.
+  if (slice != NULL) {
+    if (!grpc_error_get_str(found_error, GRPC_ERROR_STR_GRPC_MESSAGE, slice)) {
+      if (!grpc_error_get_str(found_error, GRPC_ERROR_STR_DESCRIPTION, slice)) {
+        *slice = grpc_slice_from_static_string("unknown error");
+      }
     }
   }
 
diff --git a/src/core/lib/transport/error_utils.h b/src/core/lib/transport/error_utils.h
index 105338880a..3b44466ab8 100644
--- a/src/core/lib/transport/error_utils.h
+++ b/src/core/lib/transport/error_utils.h
@@ -44,7 +44,7 @@
 /// attributes (code, msg, http_status) are unneeded, they can be passed as
 /// NULL.
 void grpc_error_get_status(grpc_error *error, gpr_timespec deadline,
-                           grpc_status_code *code, const char **msg,
+                           grpc_status_code *code, grpc_slice *slice,
                            grpc_http2_error_code *http_status);
 
 /// A utility function to check whether there is a clear status code that
diff --git a/src/core/lib/transport/metadata_batch.c b/src/core/lib/transport/metadata_batch.c
index fc2c52bd8a..fa73244aa4 100644
--- a/src/core/lib/transport/metadata_batch.c
+++ b/src/core/lib/transport/metadata_batch.c
@@ -101,12 +101,10 @@ void grpc_metadata_batch_destroy(grpc_exec_ctx *exec_ctx,
 }
 
 grpc_error *grpc_attach_md_to_error(grpc_error *src, grpc_mdelem md) {
-  char *k = grpc_slice_to_c_string(GRPC_MDKEY(md));
-  char *v = grpc_slice_to_c_string(GRPC_MDVALUE(md));
   grpc_error *out = grpc_error_set_str(
-      grpc_error_set_str(src, GRPC_ERROR_STR_KEY, k), GRPC_ERROR_STR_VALUE, v);
-  gpr_free(k);
-  gpr_free(v);
+      grpc_error_set_str(src, GRPC_ERROR_STR_KEY,
+                         grpc_slice_ref_internal(GRPC_MDKEY(md))),
+      GRPC_ERROR_STR_VALUE, grpc_slice_ref_internal(GRPC_MDVALUE(md)));
   return out;
 }
 
@@ -126,7 +124,8 @@ static grpc_error *maybe_link_callout(grpc_metadata_batch *batch,
     return GRPC_ERROR_NONE;
   }
   return grpc_attach_md_to_error(
-      GRPC_ERROR_CREATE("Unallowed duplicate metadata"), storage->md);
+      GRPC_ERROR_CREATE_FROM_STATIC_STRING("Unallowed duplicate metadata"),
+      storage->md);
 }
 
 static void maybe_unlink_callout(grpc_metadata_batch *batch,
@@ -302,7 +301,7 @@ static void add_error(grpc_error **composite, grpc_error *error,
                       const char *composite_error_string) {
   if (error == GRPC_ERROR_NONE) return;
   if (*composite == GRPC_ERROR_NONE) {
-    *composite = GRPC_ERROR_CREATE(composite_error_string);
+    *composite = GRPC_ERROR_CREATE_FROM_COPIED_STRING(composite_error_string);
   }
   *composite = grpc_error_add_child(*composite, error);
 }
diff --git a/src/core/lib/transport/service_config.c b/src/core/lib/transport/service_config.c
index 12da2a88fe..1195f75044 100644
--- a/src/core/lib/transport/service_config.c
+++ b/src/core/lib/transport/service_config.c
@@ -93,6 +93,18 @@ void grpc_service_config_destroy(grpc_service_config* service_config) {
   gpr_free(service_config);
 }
 
+void grpc_service_config_parse_global_params(
+    const grpc_service_config* service_config,
+    void (*process_json)(const grpc_json* json, void* arg), void* arg) {
+  const grpc_json* json = service_config->json_tree;
+  if (json->type != GRPC_JSON_OBJECT || json->key != NULL) return;
+  for (grpc_json* field = json->child; field != NULL; field = field->next) {
+    if (field->key == NULL) return;
+    if (strcmp(field->key, "methodConfig") == 0) continue;
+    process_json(field, arg);
+  }
+}
+
 const char* grpc_service_config_get_lb_policy_name(
     const grpc_service_config* service_config) {
   const grpc_json* json = service_config->json_tree;
diff --git a/src/core/lib/transport/service_config.h b/src/core/lib/transport/service_config.h
index cd739a593c..ebfc59b534 100644
--- a/src/core/lib/transport/service_config.h
+++ b/src/core/lib/transport/service_config.h
@@ -42,6 +42,12 @@ typedef struct grpc_service_config grpc_service_config;
 grpc_service_config* grpc_service_config_create(const char* json_string);
 void grpc_service_config_destroy(grpc_service_config* service_config);
 
+/// Invokes \a process_json() for each global parameter in the service
+/// config.  \a arg is passed as the second argument to \a process_json().
+void grpc_service_config_parse_global_params(
+    const grpc_service_config* service_config,
+    void (*process_json)(const grpc_json* json, void* arg), void* arg);
+
 /// Gets the LB policy name from \a service_config.
 /// Returns NULL if no LB policy name was specified.
 /// Caller does NOT take ownership.