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#ifndef TARANTOOL_HISTOGRAM_H_INCLUDED
#define TARANTOOL_HISTOGRAM_H_INCLUDED
/*
* Copyright 2010-2016, Tarantool AUTHORS, please see AUTHORS file.
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* 1. Redistributions of source code must retain the above
* copyright notice, this list of conditions and the
* following disclaimer.
*
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``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
* <COPYRIGHT HOLDER> 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.
*/
#if defined(__cplusplus)
extern "C" {
#endif
#include <stddef.h>
#include <stdint.h>
#include <assert.h>
struct histogram_bucket {
int64_t max;
size_t count;
};
struct histogram {
int64_t max;
size_t total;
size_t n_buckets;
struct histogram_bucket buckets[0];
};
/**
* Create a new histogram given an array of bucket boundaries.
* buckets[i] defines the upper bound for bucket i.
*/
struct histogram *
histogram_new(const int64_t *buckets, size_t n_buckets);
/**
* Destroy a histogram.
*/
void
histogram_delete(struct histogram *hist);
/**
* Reset a histogram.
*/
void
histogram_reset(struct histogram *hist);
/**
* Update a histogram with a new observation.
*/
void
histogram_collect(struct histogram *hist, int64_t val);
/**
* Remove a previously collected observation from a historam.
*/
void
histogram_discard(struct histogram *hist, int64_t val);
/**
* Calculate a percentile, i.e. the value below which a given
* percentage of observations fall.
*/
int64_t
histogram_percentile(struct histogram *hist, int pct);
/**
* Same as histogram_percentile(), but return a lower bound
* estimate of the percentile.
*/
int64_t
histogram_percentile_lower(struct histogram *hist, int pct);
/**
* Print string representation of a histogram.
*/
int
histogram_snprint(char *buf, int size, struct histogram *hist);
#if defined(__cplusplus)
} /* extern "C" */
#endif
#endif /* TARANTOOL_HISTOGRAM_H_INCLUDED */
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