1 /* 2 * util/timehist.h - make histogram of time values. 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file contains functions to make a histogram of time values. 40 */ 41 42 #ifndef UTIL_TIMEHIST_H 43 #define UTIL_TIMEHIST_H 44 45 /** Number of buckets in a histogram */ 46 #define NUM_BUCKETS_HIST 40 47 48 /** 49 * Bucket of time history information 50 */ 51 struct th_buck { 52 /** lower bound */ 53 struct timeval lower; 54 /** upper bound */ 55 struct timeval upper; 56 /** number of items */ 57 size_t count; 58 }; 59 60 /** 61 * Keep histogram of time values. 62 */ 63 struct timehist { 64 /** number of buckets */ 65 size_t num; 66 /** bucket array */ 67 struct th_buck* buckets; 68 }; 69 70 /** 71 * Setup a histogram, default 72 * @return histogram or NULL on malloc failure. 73 */ 74 struct timehist* timehist_setup(void); 75 76 /** 77 * Delete histogram 78 * @param hist: to delete 79 */ 80 void timehist_delete(struct timehist* hist); 81 82 /** 83 * Clear histogram 84 * @param hist: to clear all data from 85 */ 86 void timehist_clear(struct timehist* hist); 87 88 /** 89 * Add time value to histogram. 90 * @param hist: histogram 91 * @param tv: time value 92 */ 93 void timehist_insert(struct timehist* hist, struct timeval* tv); 94 95 /** 96 * Find time value for given quartile, such as 0.25, 0.50, 0.75. 97 * The looks up the value for the i-th element in the sorted list of time 98 * values, as approximated using the histogram. 99 * @param hist: histogram. Interpolated information is used from it. 100 * @param q: quartile, 0.50 results in the median. Must be >0 and <1. 101 * @return: the time in seconds for that percentage. 102 */ 103 double timehist_quartile(struct timehist* hist, double q); 104 105 /** 106 * Printout histogram 107 * @param hist: histogram 108 */ 109 void timehist_print(struct timehist* hist); 110 111 /** 112 * Log histogram, print it to the logfile. 113 * @param hist: histogram 114 * @param name: the name of the value column 115 */ 116 void timehist_log(struct timehist* hist, const char* name); 117 118 /** 119 * Export histogram to an array. 120 * @param hist: histogram 121 * @param array: the array to export to. 122 * @param sz: number of items in array. 123 */ 124 void timehist_export(struct timehist* hist, size_t* array, size_t sz); 125 126 /** 127 * Import histogram from an array. 128 * @param hist: histogram 129 * @param array: the array to import from. 130 * @param sz: number of items in array. 131 */ 132 void timehist_import(struct timehist* hist, size_t* array, size_t sz); 133 134 #endif /* UTIL_TIMEHIST_H */ 135