aboutsummaryrefslogtreecommitdiffhomepage
path: root/src/core/ext/census/window_stats.cc
diff options
context:
space:
mode:
Diffstat (limited to 'src/core/ext/census/window_stats.cc')
-rw-r--r--src/core/ext/census/window_stats.cc301
1 files changed, 0 insertions, 301 deletions
diff --git a/src/core/ext/census/window_stats.cc b/src/core/ext/census/window_stats.cc
deleted file mode 100644
index 0058e4bf9c..0000000000
--- a/src/core/ext/census/window_stats.cc
+++ /dev/null
@@ -1,301 +0,0 @@
-/*
- *
- * 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 "src/core/ext/census/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);
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-07 12:14:57 +0000