001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, software 013 * distributed under the License is distributed on an "AS IS" BASIS, 014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 015 * See the License for the specific language governing permissions and 016 * limitations under the License. 017 */ 018package org.apache.hadoop.hbase.metrics; 019 020import org.apache.yetus.audience.InterfaceAudience; 021 022/** 023 * A statictical sample of histogram values. 024 */ 025@InterfaceAudience.Private 026public interface Snapshot { 027 028 /** 029 * Return the values with the given quantiles. 030 * @param quantiles the requested quantiles. 031 * @return the value for the quantiles. 032 */ 033 long[] getQuantiles(double[] quantiles); 034 035 /** 036 * Return the values with the default quantiles. 037 * @return the value for default the quantiles. 038 */ 039 long[] getQuantiles(); 040 041 /** 042 * Returns the number of values in the snapshot. 043 * @return the number of values 044 */ 045 long getCount(); 046 047 /** 048 * Returns the total count below the given value 049 * @param val the value 050 * @return the total count below the given value 051 */ 052 long getCountAtOrBelow(long val); 053 054 /** 055 * Returns the value at the 25th percentile in the distribution. 056 * @return the value at the 25th percentile 057 */ 058 long get25thPercentile(); 059 060 /** 061 * Returns the value at the 75th percentile in the distribution. 062 * @return the value at the 75th percentile 063 */ 064 long get75thPercentile(); 065 066 /** 067 * Returns the value at the 90th percentile in the distribution. 068 * @return the value at the 90th percentile 069 */ 070 long get90thPercentile(); 071 072 /** 073 * Returns the value at the 95th percentile in the distribution. 074 * @return the value at the 95th percentile 075 */ 076 long get95thPercentile(); 077 078 /** 079 * Returns the value at the 98th percentile in the distribution. 080 * @return the value at the 98th percentile 081 */ 082 long get98thPercentile(); 083 084 /** 085 * Returns the value at the 99th percentile in the distribution. 086 * @return the value at the 99th percentile 087 */ 088 long get99thPercentile(); 089 090 /** 091 * Returns the value at the 99.9th percentile in the distribution. 092 * @return the value at the 99.9th percentile 093 */ 094 long get999thPercentile(); 095 096 /** 097 * Returns the median value in the distribution. 098 * @return the median value 099 */ 100 long getMedian(); 101 102 /** 103 * Returns the highest value in the snapshot. 104 * @return the highest value 105 */ 106 long getMax(); 107 108 /** 109 * Returns the arithmetic mean of the values in the snapshot. 110 * @return the arithmetic mean 111 */ 112 long getMean(); 113 114 /** 115 * Returns the lowest value in the snapshot. 116 * @return the lowest value 117 */ 118 long getMin(); 119 120 // TODO: Dropwizard histograms also track stddev 121}