3 files changed, 22 insertions, 1 deletions
diff --git a/src/core/surface/byte_buffer_queue.c b/src/core/surface/byte_buffer_queue.c
index 7c31bfe5da..e47dc4f4ce 100644
--- a/src/core/surface/byte_buffer_queue.c
+++ b/src/core/surface/byte_buffer_queue.c
@@ -62,6 +62,7 @@ int grpc_bbq_empty(grpc_byte_buffer_queue *q) {
 }
 
 void grpc_bbq_push(grpc_byte_buffer_queue *q, grpc_byte_buffer *buffer) {
+  q->bytes += grpc_byte_buffer_length(buffer);
   bba_push(&q->filling, buffer);
 }
 
@@ -72,8 +73,11 @@ void grpc_bbq_flush(grpc_byte_buffer_queue *q) {
   }
 }
 
+size_t grpc_bbq_bytes(grpc_byte_buffer_queue *q) { return q->bytes; }
+
 grpc_byte_buffer *grpc_bbq_pop(grpc_byte_buffer_queue *q) {
   grpc_bbq_array temp_array;
+  grpc_byte_buffer *out;
 
   if (q->drain_pos == q->draining.count) {
     if (q->filling.count == 0) {
@@ -87,5 +91,7 @@ grpc_byte_buffer *grpc_bbq_pop(grpc_byte_buffer_queue *q) {
     q->draining = temp_array;
   }
 
-  return q->draining.data[q->drain_pos++];
+  out = q->draining.data[q->drain_pos++];
+  q->bytes -= grpc_byte_buffer_length(out);
+  return out;
 }
diff --git a/src/core/surface/byte_buffer_queue.h b/src/core/surface/byte_buffer_queue.h
index 32c57f8756..f01958984f 100644
--- a/src/core/surface/byte_buffer_queue.h
+++ b/src/core/surface/byte_buffer_queue.h
@@ -49,6 +49,7 @@ typedef struct {
   size_t drain_pos;
   grpc_bbq_array filling;
   grpc_bbq_array draining;
+  size_t bytes;
 } grpc_byte_buffer_queue;
 
 void grpc_bbq_destroy(grpc_byte_buffer_queue *q);
@@ -56,5 +57,6 @@ grpc_byte_buffer *grpc_bbq_pop(grpc_byte_buffer_queue *q);
 void grpc_bbq_flush(grpc_byte_buffer_queue *q);
 int grpc_bbq_empty(grpc_byte_buffer_queue *q);
 void grpc_bbq_push(grpc_byte_buffer_queue *q, grpc_byte_buffer *bb);
+size_t grpc_bbq_bytes(grpc_byte_buffer_queue *q);
 
 #endif  /* GRPC_INTERNAL_CORE_SURFACE_BYTE_BUFFER_QUEUE_H */
diff --git a/src/core/surface/call.c b/src/core/surface/call.c
index 0a551ac47f..71f4235571 100644
--- a/src/core/surface/call.c
+++ b/src/core/surface/call.c
@@ -513,6 +513,8 @@ static void unlock(grpc_call *call) {
   int completing_requests = 0;
   int start_op = 0;
   int i;
+  const gpr_uint32 MAX_RECV_PEEK_AHEAD = 65536;
+  size_t buffered_bytes;
   int cancel_alarm = 0;
 
   memset(&op, 0, sizeof(op));
@@ -528,6 +530,17 @@ static void unlock(grpc_call *call) {
     op.recv_ops = &call->recv_ops;
     op.recv_state = &call->recv_state;
     op.on_done_recv = &call->on_done_recv;
+    if (grpc_bbq_empty(&call->incoming_queue) && call->reading_message) {
+      op.max_recv_bytes = call->incoming_message_length -
+                          call->incoming_message.length + MAX_RECV_PEEK_AHEAD;
+    } else {
+      buffered_bytes = grpc_bbq_bytes(&call->incoming_queue);
+      if (buffered_bytes > MAX_RECV_PEEK_AHEAD) {
+        op.max_recv_bytes = 0;
+      } else {
+        op.max_recv_bytes = MAX_RECV_PEEK_AHEAD - buffered_bytes;
+      }
+    }
     call->receiving = 1;
     GRPC_CALL_INTERNAL_REF(call, "receiving");
     start_op = 1;