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.io.hfile; 019 020import org.apache.hadoop.hbase.metrics.impl.FastLongHistogram; 021import org.apache.yetus.audience.InterfaceAudience; 022 023/** 024 * Snapshot of block cache age in cache. This object is preferred because we can control how it is 025 * serialized out when JSON'ing. 026 */ 027@InterfaceAudience.Private 028public class AgeSnapshot { 029 030 private transient final FastLongHistogram ageHistogram; 031 private transient final long[] quantiles; 032 033 AgeSnapshot(final FastLongHistogram ageHistogram) { 034 this.ageHistogram = ageHistogram; 035 this.quantiles = ageHistogram.getQuantiles(new double[] { 0.75, 0.95, 0.98, 0.99, 0.999 }); 036 } 037 038 public double get75thPercentile() { 039 return quantiles[0]; 040 } 041 042 public double get95thPercentile() { 043 return quantiles[1]; 044 } 045 046 public double get98thPercentile() { 047 return quantiles[2]; 048 } 049 050 public double get99thPercentile() { 051 return quantiles[3]; 052 } 053 054 public double get999thPercentile() { 055 return quantiles[4]; 056 } 057 058 public double getMean() { 059 return this.ageHistogram.getMean(); 060 } 061 062 public double getMax() { 063 return this.ageHistogram.getMax(); 064 } 065 066 public double getMin() { 067 return this.ageHistogram.getMin(); 068 } 069}