/*
* util/timehist.h - make histogram of time values.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* 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 the NLNET LABS 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
* 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.
*/
/**
* \file
*
* This file contains functions to make a histogram of time values.
*/
#ifndef UTIL_TIMEHIST_H
#define UTIL_TIMEHIST_H
/** Number of buckets in a histogram */
#define NUM_BUCKETS_HIST 40
/**
* Bucket of time history information
*/
struct th_buck {
/** lower bound */
struct timeval lower;
/** upper bound */
struct timeval upper;
/** number of items */
size_t count;
};
/**
* Keep histogram of time values.
*/
struct timehist {
/** number of buckets */
size_t num;
/** bucket array */
struct th_buck* buckets;
};
/**
* Setup a histogram, default
* @return histogram or NULL on malloc failure.
*/
struct timehist* timehist_setup(void);
/**
* Delete histogram
* @param hist: to delete
*/
void timehist_delete(struct timehist* hist);
/**
* Clear histogram
* @param hist: to clear all data from
*/
void timehist_clear(struct timehist* hist);
/**
* Add time value to histogram.
* @param hist: histogram
* @param tv: time value
*/
void timehist_insert(struct timehist* hist, struct timeval* tv);
/**
* Find time value for given quartile, such as 0.25, 0.50, 0.75.
* The looks up the value for the i-th element in the sorted list of time
* values, as approximated using the histogram.
* @param hist: histogram. Interpolated information is used from it.
* @param q: quartile, 0.50 results in the median. Must be >0 and <1.
* @return: the time in seconds for that percentage.
*/
double timehist_quartile(struct timehist* hist, double q);
/**
* Printout histogram
* @param hist: histogram
*/
void timehist_print(struct timehist* hist);
/**
* Log histogram, print it to the logfile.
* @param hist: histogram
* @param name: the name of the value column
*/
void timehist_log(struct timehist* hist, const char* name);
/**
* Export histogram to an array.
* @param hist: histogram
* @param array: the array to export to.
* @param sz: number of items in array.
*/
void timehist_export(struct timehist* hist, size_t* array, size_t sz);
/**
* Import histogram from an array.
* @param hist: histogram
* @param array: the array to import from.
* @param sz: number of items in array.
*/
void timehist_import(struct timehist* hist, size_t* array, size_t sz);
#endif /* UTIL_TIMEHIST_H */
