diff options
author | Craig Tiller <ctiller@google.com> | 2016-03-25 17:07:29 -0700 |
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committer | Craig Tiller <ctiller@google.com> | 2016-03-25 17:07:29 -0700 |
commit | f23078cbd302d32649537eedda1769c5685228d8 (patch) | |
tree | b0bb46845658e5b8256868d102076226aa10215e /src/core/statistics/window_stats.c | |
parent | f3d76384351039266e250aacf97c90d5b0c07dca (diff) |
Stage #1 of core breakup: move everything under lib
Diffstat (limited to 'src/core/statistics/window_stats.c')
-rw-r--r-- | src/core/statistics/window_stats.c | 316 |
1 files changed, 0 insertions, 316 deletions
diff --git a/src/core/statistics/window_stats.c b/src/core/statistics/window_stats.c deleted file mode 100644 index eb296865a0..0000000000 --- a/src/core/statistics/window_stats.c +++ /dev/null @@ -1,316 +0,0 @@ -/* - * - * Copyright 2015-2016, Google Inc. - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are - * met: - * - * * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * * Redistributions in binary form must reproduce the above - * copyright notice, this list of conditions and the following disclaimer - * in the documentation and/or other materials provided with the - * distribution. - * * Neither the name of Google Inc. nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - * - */ - -#include "src/core/statistics/window_stats.h" -#include <grpc/support/alloc.h> -#include <grpc/support/log.h> -#include <grpc/support/time.h> -#include <grpc/support/useful.h> -#include <math.h> -#include <stddef.h> -#include <string.h> - -/* typedefs make typing long names easier. Use cws (for census_window_stats) */ -typedef census_window_stats_stat_info cws_stat_info; -typedef struct census_window_stats_sum cws_sum; - -/* Each interval is composed of a number of buckets, which hold a count of - entries and a single statistic */ -typedef struct census_window_stats_bucket { - int64_t count; - void *statistic; -} cws_bucket; - -/* Each interval has a set of buckets, and the variables needed to keep - track of their current state */ -typedef struct census_window_stats_interval_stats { - /* The buckets. There will be 'granularity' + 1 of these. */ - cws_bucket *buckets; - /* Index of the bucket containing the smallest time interval. */ - int bottom_bucket; - /* The smallest time storable in the current window. */ - int64_t bottom; - /* The largest time storable in the current window + 1ns */ - int64_t top; - /* The width of each bucket in ns. */ - int64_t width; -} cws_interval_stats; - -typedef struct census_window_stats { - /* Number of intervals. */ - int nintervals; - /* Number of buckets in each interval. 'granularity' + 1. */ - int nbuckets; - /* Record of stat_info. */ - cws_stat_info stat_info; - /* Stats for each interval. */ - cws_interval_stats *interval_stats; - /* The time the newset stat was recorded. */ - int64_t newest_time; -} window_stats; - -/* Calculate an actual bucket index from a logical index 'IDX'. Other - parameters supply information on the interval struct and overall stats. */ -#define BUCKET_IDX(IS, IDX, WSTATS) \ - ((IS->bottom_bucket + (IDX)) % WSTATS->nbuckets) - -/* The maximum seconds value we can have in a valid timespec. More than this - will result in overflow in timespec_to_ns(). This works out to ~292 years. - TODO: consider using doubles instead of int64. */ -static int64_t max_seconds = (GPR_INT64_MAX - GPR_NS_PER_SEC) / GPR_NS_PER_SEC; - -static int64_t timespec_to_ns(const gpr_timespec ts) { - if (ts.tv_sec > max_seconds) { - return GPR_INT64_MAX - 1; - } - return ts.tv_sec * GPR_NS_PER_SEC + ts.tv_nsec; -} - -static void cws_initialize_statistic(void *statistic, - const cws_stat_info *stat_info) { - if (stat_info->stat_initialize == NULL) { - memset(statistic, 0, stat_info->stat_size); - } else { - stat_info->stat_initialize(statistic); - } -} - -/* Create and initialize a statistic */ -static void *cws_create_statistic(const cws_stat_info *stat_info) { - void *stat = gpr_malloc(stat_info->stat_size); - cws_initialize_statistic(stat, stat_info); - return stat; -} - -window_stats *census_window_stats_create(int nintervals, - const gpr_timespec intervals[], - int granularity, - const cws_stat_info *stat_info) { - window_stats *ret; - int i; - /* validate inputs */ - GPR_ASSERT(nintervals > 0 && granularity > 2 && intervals != NULL && - stat_info != NULL); - for (i = 0; i < nintervals; i++) { - int64_t ns = timespec_to_ns(intervals[i]); - GPR_ASSERT(intervals[i].tv_sec >= 0 && intervals[i].tv_nsec >= 0 && - intervals[i].tv_nsec < GPR_NS_PER_SEC && ns >= 100 && - granularity * 10 <= ns); - } - /* Allocate and initialize relevant data structures */ - ret = (window_stats *)gpr_malloc(sizeof(window_stats)); - ret->nintervals = nintervals; - ret->nbuckets = granularity + 1; - ret->stat_info = *stat_info; - ret->interval_stats = - (cws_interval_stats *)gpr_malloc(nintervals * sizeof(cws_interval_stats)); - for (i = 0; i < nintervals; i++) { - int64_t size_ns = timespec_to_ns(intervals[i]); - cws_interval_stats *is = ret->interval_stats + i; - cws_bucket *buckets = is->buckets = - (cws_bucket *)gpr_malloc(ret->nbuckets * sizeof(cws_bucket)); - int b; - for (b = 0; b < ret->nbuckets; b++) { - buckets[b].statistic = cws_create_statistic(stat_info); - buckets[b].count = 0; - } - is->bottom_bucket = 0; - is->bottom = 0; - is->width = size_ns / granularity; - /* Check for possible overflow issues, and maximize interval size if the - user requested something large enough. */ - if ((GPR_INT64_MAX - is->width) > size_ns) { - is->top = size_ns + is->width; - } else { - is->top = GPR_INT64_MAX; - is->width = GPR_INT64_MAX / (granularity + 1); - } - /* If size doesn't divide evenly, we can have a width slightly too small; - better to have it slightly large. */ - if ((size_ns - (granularity + 1) * is->width) > 0) { - is->width += 1; - } - } - ret->newest_time = 0; - return ret; -} - -/* When we try adding a measurement above the current interval range, we - need to "shift" the buckets sufficiently to cover the new range. */ -static void cws_shift_buckets(const window_stats *wstats, - cws_interval_stats *is, int64_t when_ns) { - int i; - /* number of bucket time widths to "shift" */ - int shift; - /* number of buckets to clear */ - int nclear; - GPR_ASSERT(when_ns >= is->top); - /* number of bucket time widths to "shift" */ - shift = ((when_ns - is->top) / is->width) + 1; - /* number of buckets to clear - limited by actual number of buckets */ - nclear = GPR_MIN(shift, wstats->nbuckets); - for (i = 0; i < nclear; i++) { - int b = BUCKET_IDX(is, i, wstats); - is->buckets[b].count = 0; - cws_initialize_statistic(is->buckets[b].statistic, &wstats->stat_info); - } - /* adjust top/bottom times and current bottom bucket */ - is->bottom_bucket = BUCKET_IDX(is, shift, wstats); - is->top += shift * is->width; - is->bottom += shift * is->width; -} - -void census_window_stats_add(window_stats *wstats, const gpr_timespec when, - const void *stat_value) { - int i; - int64_t when_ns = timespec_to_ns(when); - GPR_ASSERT(wstats->interval_stats != NULL); - for (i = 0; i < wstats->nintervals; i++) { - cws_interval_stats *is = wstats->interval_stats + i; - cws_bucket *bucket; - if (when_ns < is->bottom) { /* Below smallest time in interval: drop */ - continue; - } - if (when_ns >= is->top) { /* above limit: shift buckets */ - cws_shift_buckets(wstats, is, when_ns); - } - /* Add the stat. */ - GPR_ASSERT(is->bottom <= when_ns && when_ns < is->top); - bucket = is->buckets + - BUCKET_IDX(is, (when_ns - is->bottom) / is->width, wstats); - bucket->count++; - wstats->stat_info.stat_add(bucket->statistic, stat_value); - } - if (when_ns > wstats->newest_time) { - wstats->newest_time = when_ns; - } -} - -/* Add a specific bucket contents to an accumulating total. */ -static void cws_add_bucket_to_sum(cws_sum *sum, const cws_bucket *bucket, - const cws_stat_info *stat_info) { - sum->count += bucket->count; - stat_info->stat_add(sum->statistic, bucket->statistic); -} - -/* Add a proportion to an accumulating sum. */ -static void cws_add_proportion_to_sum(double p, cws_sum *sum, - const cws_bucket *bucket, - const cws_stat_info *stat_info) { - sum->count += p * bucket->count; - stat_info->stat_add_proportion(p, sum->statistic, bucket->statistic); -} - -void census_window_stats_get_sums(const window_stats *wstats, - const gpr_timespec when, cws_sum sums[]) { - int i; - int64_t when_ns = timespec_to_ns(when); - GPR_ASSERT(wstats->interval_stats != NULL); - for (i = 0; i < wstats->nintervals; i++) { - int when_bucket; - int new_bucket; - double last_proportion = 1.0; - double bottom_proportion; - cws_interval_stats *is = wstats->interval_stats + i; - cws_sum *sum = sums + i; - sum->count = 0; - cws_initialize_statistic(sum->statistic, &wstats->stat_info); - if (when_ns < is->bottom) { - continue; - } - if (when_ns >= is->top) { - cws_shift_buckets(wstats, is, when_ns); - } - /* Calculating the appropriate amount of which buckets to use can get - complicated. Essentially there are two cases: - 1) if the "top" bucket (new_bucket, where the newest additions to the - stats recorded are entered) corresponds to 'when', then we need - to take a proportion of it - (if when < newest_time) or the full - thing. We also (possibly) need to take a corresponding - proportion of the bottom bucket. - 2) Other cases, we just take a straight proportion. - */ - when_bucket = (when_ns - is->bottom) / is->width; - new_bucket = (wstats->newest_time - is->bottom) / is->width; - if (new_bucket == when_bucket) { - int64_t bottom_bucket_time = is->bottom + when_bucket * is->width; - if (when_ns < wstats->newest_time) { - last_proportion = (double)(when_ns - bottom_bucket_time) / - (double)(wstats->newest_time - bottom_bucket_time); - bottom_proportion = - (double)(is->width - (when_ns - bottom_bucket_time)) / is->width; - } else { - bottom_proportion = - (double)(is->width - (wstats->newest_time - bottom_bucket_time)) / - is->width; - } - } else { - last_proportion = - (double)(when_ns + 1 - is->bottom - when_bucket * is->width) / - is->width; - bottom_proportion = 1.0 - last_proportion; - } - cws_add_proportion_to_sum(last_proportion, sum, - is->buckets + BUCKET_IDX(is, when_bucket, wstats), - &wstats->stat_info); - if (when_bucket != 0) { /* last bucket isn't also bottom bucket */ - int b; - /* Add all of "bottom" bucket if we are looking at a subset of the - full interval, or a proportion if we are adding full interval. */ - cws_add_proportion_to_sum( - (when_bucket == wstats->nbuckets - 1 ? bottom_proportion : 1.0), sum, - is->buckets + is->bottom_bucket, &wstats->stat_info); - /* Add all the remaining buckets (everything but top and bottom). */ - for (b = 1; b < when_bucket; b++) { - cws_add_bucket_to_sum(sum, is->buckets + BUCKET_IDX(is, b, wstats), - &wstats->stat_info); - } - } - } -} - -void census_window_stats_destroy(window_stats *wstats) { - int i; - GPR_ASSERT(wstats->interval_stats != NULL); - for (i = 0; i < wstats->nintervals; i++) { - int b; - for (b = 0; b < wstats->nbuckets; b++) { - gpr_free(wstats->interval_stats[i].buckets[b].statistic); - } - gpr_free(wstats->interval_stats[i].buckets); - } - gpr_free(wstats->interval_stats); - /* Ensure any use-after free triggers assert. */ - wstats->interval_stats = NULL; - gpr_free(wstats); -} |