1 // 2 // 3 // Copyright 2016 gRPC authors. 4 // 5 // Licensed under the Apache License, Version 2.0 (the "License"); 6 // you may not use this file except in compliance with the License. 7 // You may obtain a copy of the License at 8 // 9 // http://www.apache.org/licenses/LICENSE-2.0 10 // 11 // Unless required by applicable law or agreed to in writing, software 12 // distributed under the License is distributed on an "AS IS" BASIS, 13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 // See the License for the specific language governing permissions and 15 // limitations under the License. 16 // 17 // 18 19 #include "src/core/util/backoff.h" 20 21 #include <grpc/support/port_platform.h> 22 23 #include <algorithm> 24 25 #include "src/core/lib/experiments/experiments.h" 26 27 namespace grpc_core { 28 BackOff(const Options & options)29BackOff::BackOff(const Options& options) : options_(options) { Reset(); } 30 NextAttemptDelay()31Duration BackOff::NextAttemptDelay() { 32 if (IsBackoffCapInitialAtMaxEnabled()) { 33 if (initial_) { 34 initial_ = false; 35 } else { 36 current_backoff_ *= options_.multiplier(); 37 } 38 current_backoff_ = std::min(current_backoff_, options_.max_backoff()); 39 } else { 40 if (initial_) { 41 initial_ = false; 42 } else { 43 current_backoff_ = std::min(current_backoff_ * options_.multiplier(), 44 options_.max_backoff()); 45 } 46 } 47 const double jitter = 48 absl::Uniform(rand_gen_, 1 - options_.jitter(), 1 + options_.jitter()); 49 return current_backoff_ * jitter; 50 } 51 Reset()52void BackOff::Reset() { 53 current_backoff_ = options_.initial_backoff(); 54 initial_ = true; 55 } 56 57 } // namespace grpc_core 58