Line data    Source code

       1             : /*
       2             :  *
       3             :  * Copyright 2015, Google Inc.
       4             :  * All rights reserved.
       5             :  *
       6             :  * Redistribution and use in source and binary forms, with or without
       7             :  * modification, are permitted provided that the following conditions are
       8             :  * met:
       9             :  *
      10             :  *     * Redistributions of source code must retain the above copyright
      11             :  * notice, this list of conditions and the following disclaimer.
      12             :  *     * Redistributions in binary form must reproduce the above
      13             :  * copyright notice, this list of conditions and the following disclaimer
      14             :  * in the documentation and/or other materials provided with the
      15             :  * distribution.
      16             :  *     * Neither the name of Google Inc. nor the names of its
      17             :  * contributors may be used to endorse or promote products derived from
      18             :  * this software without specific prior written permission.
      19             :  *
      20             :  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      21             :  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      22             :  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      23             :  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      24             :  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      25             :  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      26             :  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      27             :  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      28             :  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      29             :  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      30             :  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
      31             :  *
      32             :  */
      33             : 
      34             : #include "src/core/iomgr/time_averaged_stats.h"
      35             : 
      36       80264 : void grpc_time_averaged_stats_init(grpc_time_averaged_stats* stats,
      37             :                                    double init_avg, double regress_weight,
      38             :                                    double persistence_factor) {
      39       80264 :   stats->init_avg = init_avg;
      40       80264 :   stats->regress_weight = regress_weight;
      41       80264 :   stats->persistence_factor = persistence_factor;
      42       80264 :   stats->batch_total_value = 0;
      43       80264 :   stats->batch_num_samples = 0;
      44       80264 :   stats->aggregate_total_weight = 0;
      45       80264 :   stats->aggregate_weighted_avg = init_avg;
      46       80264 : }
      47             : 
      48       10866 : void grpc_time_averaged_stats_add_sample(grpc_time_averaged_stats* stats,
      49             :                                          double value) {
      50       10866 :   stats->batch_total_value += value;
      51       10866 :   ++stats->batch_num_samples;
      52       10866 : }
      53             : 
      54      190981 : double grpc_time_averaged_stats_update_average(
      55             :     grpc_time_averaged_stats* stats) {
      56             :   /* Start with the current batch: */
      57      190981 :   double weighted_sum = stats->batch_total_value;
      58      190981 :   double total_weight = stats->batch_num_samples;
      59      190981 :   if (stats->regress_weight > 0) {
      60             :     /* Add in the regression towards init_avg_: */
      61      190971 :     weighted_sum += stats->regress_weight * stats->init_avg;
      62      190971 :     total_weight += stats->regress_weight;
      63             :   }
      64      190981 :   if (stats->persistence_factor > 0) {
      65             :     /* Add in the persistence: */
      66      190971 :     const double prev_sample_weight =
      67      190971 :         stats->persistence_factor * stats->aggregate_total_weight;
      68      190971 :     weighted_sum += prev_sample_weight * stats->aggregate_weighted_avg;
      69      190971 :     total_weight += prev_sample_weight;
      70             :   }
      71      190981 :   stats->aggregate_weighted_avg =
      72      190981 :       (total_weight > 0) ? (weighted_sum / total_weight) : stats->init_avg;
      73      190981 :   stats->aggregate_total_weight = total_weight;
      74      190981 :   stats->batch_num_samples = 0;
      75      190981 :   stats->batch_total_value = 0;
      76      190981 :   return stats->aggregate_weighted_avg;
      77             : }