| /* |
| * |
| * Copyright 2015 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 <grpc/support/port_platform.h> |
| |
| #include "src/core/lib/iomgr/time_averaged_stats.h" |
| |
| void grpc_time_averaged_stats_init(grpc_time_averaged_stats* stats, |
| double init_avg, double regress_weight, |
| double persistence_factor) { |
| stats->init_avg = init_avg; |
| stats->regress_weight = regress_weight; |
| stats->persistence_factor = persistence_factor; |
| stats->batch_total_value = 0; |
| stats->batch_num_samples = 0; |
| stats->aggregate_total_weight = 0; |
| stats->aggregate_weighted_avg = init_avg; |
| } |
| |
| void grpc_time_averaged_stats_add_sample(grpc_time_averaged_stats* stats, |
| double value) { |
| stats->batch_total_value += value; |
| ++stats->batch_num_samples; |
| } |
| |
| double grpc_time_averaged_stats_update_average( |
| grpc_time_averaged_stats* stats) { |
| /* Start with the current batch: */ |
| double weighted_sum = stats->batch_total_value; |
| double total_weight = stats->batch_num_samples; |
| if (stats->regress_weight > 0) { |
| /* Add in the regression towards init_avg_: */ |
| weighted_sum += stats->regress_weight * stats->init_avg; |
| total_weight += stats->regress_weight; |
| } |
| if (stats->persistence_factor > 0) { |
| /* Add in the persistence: */ |
| const double prev_sample_weight = |
| stats->persistence_factor * stats->aggregate_total_weight; |
| weighted_sum += prev_sample_weight * stats->aggregate_weighted_avg; |
| total_weight += prev_sample_weight; |
| } |
| stats->aggregate_weighted_avg = |
| (total_weight > 0) ? (weighted_sum / total_weight) : stats->init_avg; |
| stats->aggregate_total_weight = total_weight; |
| stats->batch_num_samples = 0; |
| stats->batch_total_value = 0; |
| return stats->aggregate_weighted_avg; |
| } |