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Diffstat (limited to 'src/core/lib/support/backoff.cc')
-rw-r--r-- | src/core/lib/support/backoff.cc | 72 |
1 files changed, 0 insertions, 72 deletions
diff --git a/src/core/lib/support/backoff.cc b/src/core/lib/support/backoff.cc deleted file mode 100644 index 6dc0df473b..0000000000 --- a/src/core/lib/support/backoff.cc +++ /dev/null @@ -1,72 +0,0 @@ -/* - * - * Copyright 2016 gRPC authors. - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - * - */ - -#include "src/core/lib/support/backoff.h" - -#include <grpc/support/useful.h> - -void gpr_backoff_init(gpr_backoff *backoff, int64_t initial_connect_timeout, - double multiplier, double jitter, - int64_t min_timeout_millis, int64_t max_timeout_millis) { - backoff->initial_connect_timeout = initial_connect_timeout; - backoff->multiplier = multiplier; - backoff->jitter = jitter; - backoff->min_timeout_millis = min_timeout_millis; - backoff->max_timeout_millis = max_timeout_millis; - backoff->rng_state = (uint32_t)gpr_now(GPR_CLOCK_REALTIME).tv_nsec; -} - -gpr_timespec gpr_backoff_begin(gpr_backoff *backoff, gpr_timespec now) { - backoff->current_timeout_millis = backoff->initial_connect_timeout; - const int64_t first_timeout = - GPR_MAX(backoff->current_timeout_millis, backoff->min_timeout_millis); - return gpr_time_add(now, gpr_time_from_millis(first_timeout, GPR_TIMESPAN)); -} - -/* Generate a random number between 0 and 1. */ -static double generate_uniform_random_number(uint32_t *rng_state) { - *rng_state = (1103515245 * *rng_state + 12345) % ((uint32_t)1 << 31); - return *rng_state / (double)((uint32_t)1 << 31); -} - -gpr_timespec gpr_backoff_step(gpr_backoff *backoff, gpr_timespec now) { - const double new_timeout_millis = - backoff->multiplier * (double)backoff->current_timeout_millis; - backoff->current_timeout_millis = - GPR_MIN((int64_t)new_timeout_millis, backoff->max_timeout_millis); - - const double jitter_range_width = backoff->jitter * new_timeout_millis; - const double jitter = - (2 * generate_uniform_random_number(&backoff->rng_state) - 1) * - jitter_range_width; - - backoff->current_timeout_millis = - (int64_t)((double)(backoff->current_timeout_millis) + jitter); - - const gpr_timespec current_deadline = gpr_time_add( - now, gpr_time_from_millis(backoff->current_timeout_millis, GPR_TIMESPAN)); - - const gpr_timespec min_deadline = gpr_time_add( - now, gpr_time_from_millis(backoff->min_timeout_millis, GPR_TIMESPAN)); - - return gpr_time_max(current_deadline, min_deadline); -} - -void gpr_backoff_reset(gpr_backoff *backoff) { - backoff->current_timeout_millis = backoff->initial_connect_timeout; -} |