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 #ifndef GRPC_CORE_LIB_TRANSPORT_BDP_ESTIMATOR_H 20 #define GRPC_CORE_LIB_TRANSPORT_BDP_ESTIMATOR_H 21 22 #include <grpc/support/port_platform.h> 23 24 #include <inttypes.h> 25 #include <stdbool.h> 26 #include <stdint.h> 27 28 #include <grpc/support/log.h> 29 #include <grpc/support/time.h> 30 31 #include "src/core/lib/debug/trace.h" 32 #include "src/core/lib/iomgr/exec_ctx.h" 33 34 extern grpc_core::TraceFlag grpc_bdp_estimator_trace; 35 36 namespace grpc_core { 37 38 class BdpEstimator { 39 public: 40 explicit BdpEstimator(const char* name); 41 ~BdpEstimator() {} 42 43 int64_t EstimateBdp() const { return estimate_; } 44 double EstimateBandwidth() const { return bw_est_; } 45 46 void AddIncomingBytes(int64_t num_bytes) { accumulator_ += num_bytes; } 47 48 // Schedule a ping: call in response to receiving a true from 49 // grpc_bdp_estimator_add_incoming_bytes once a ping has been scheduled by a 50 // transport (but not necessarily started) 51 void SchedulePing() { 52 if (grpc_bdp_estimator_trace.enabled()) { 53 gpr_log(GPR_INFO, "bdp[%s]:sched acc=%" PRId64 " est=%" PRId64, name_, 54 accumulator_, estimate_); 55 } 56 GPR_ASSERT(ping_state_ == PingState::UNSCHEDULED); 57 ping_state_ = PingState::SCHEDULED; 58 accumulator_ = 0; 59 } 60 61 // Start a ping: call after calling grpc_bdp_estimator_schedule_ping and 62 // once 63 // the ping is on the wire 64 void StartPing() { 65 if (grpc_bdp_estimator_trace.enabled()) { 66 gpr_log(GPR_INFO, "bdp[%s]:start acc=%" PRId64 " est=%" PRId64, name_, 67 accumulator_, estimate_); 68 } 69 GPR_ASSERT(ping_state_ == PingState::SCHEDULED); 70 ping_state_ = PingState::STARTED; 71 accumulator_ = 0; 72 ping_start_time_ = gpr_now(GPR_CLOCK_MONOTONIC); 73 } 74 75 // Completes a previously started ping, returns when to schedule the next one 76 grpc_millis CompletePing(); 77 78 private: 79 enum class PingState { UNSCHEDULED, SCHEDULED, STARTED }; 80 81 PingState ping_state_; 82 int64_t accumulator_; 83 int64_t estimate_; 84 // when was the current ping started? 85 gpr_timespec ping_start_time_; 86 int inter_ping_delay_; 87 int stable_estimate_count_; 88 double bw_est_; 89 const char* name_; 90 }; 91 92 } // namespace grpc_core 93 94 #endif /* GRPC_CORE_LIB_TRANSPORT_BDP_ESTIMATOR_H */ 95
