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 */
018
019package org.apache.hadoop.metrics2.lib;
020
021import org.apache.commons.lang3.StringUtils;
022import org.apache.hadoop.hbase.metrics.Histogram;
023import org.apache.hadoop.hbase.metrics.Interns;
024import org.apache.hadoop.hbase.metrics.Snapshot;
025import org.apache.hadoop.hbase.metrics.impl.HistogramImpl;
026import org.apache.hadoop.metrics2.MetricHistogram;
027import org.apache.hadoop.metrics2.MetricsInfo;
028import org.apache.hadoop.metrics2.MetricsRecordBuilder;
029import org.apache.yetus.audience.InterfaceAudience;
030
031/**
032 * A histogram implementation that runs in constant space, and exports to hadoop2's metrics2 system.
033 */
034@InterfaceAudience.Private
035public class MutableHistogram extends MutableMetric implements MetricHistogram {
036  protected HistogramImpl histogram;
037  protected final String name;
038  protected final String desc;
039
040  public MutableHistogram(MetricsInfo info) {
041    this(info.name(), info.description());
042  }
043
044  public MutableHistogram(String name, String description) {
045    this.name = StringUtils.capitalize(name);
046    this.desc = StringUtils.uncapitalize(description);
047    this.histogram = new HistogramImpl();
048  }
049
050  public void add(final long val) {
051    histogram.update(val);
052  }
053
054  public long getMax() {
055    return histogram.getMax();
056  }
057
058  @Override
059  public synchronized void snapshot(MetricsRecordBuilder metricsRecordBuilder, boolean all) {
060    snapshot(name, desc, histogram, metricsRecordBuilder, all);
061  }
062
063  public static void snapshot(String name, String desc, Histogram histogram,
064                              MetricsRecordBuilder metricsRecordBuilder, boolean all) {
065    // Get a reference to the old histogram.
066    Snapshot snapshot = histogram.snapshot();
067    if (snapshot != null) {
068      updateSnapshotMetrics(name, desc, histogram, snapshot, metricsRecordBuilder);
069    }
070  }
071
072  protected static void updateSnapshotMetrics(String name, String desc, Histogram histogram,
073      Snapshot snapshot, MetricsRecordBuilder metricsRecordBuilder) {
074    metricsRecordBuilder.addCounter(Interns.info(name + NUM_OPS_METRIC_NAME, desc),
075        histogram.getCount());
076    metricsRecordBuilder.addGauge(Interns.info(name + MIN_METRIC_NAME, desc), snapshot.getMin());
077    metricsRecordBuilder.addGauge(Interns.info(name + MAX_METRIC_NAME, desc), snapshot.getMax());
078    metricsRecordBuilder.addGauge(Interns.info(name + MEAN_METRIC_NAME, desc), snapshot.getMean());
079
080    metricsRecordBuilder.addGauge(Interns.info(name + TWENTY_FIFTH_PERCENTILE_METRIC_NAME, desc),
081        snapshot.get25thPercentile());
082    metricsRecordBuilder.addGauge(Interns.info(name + MEDIAN_METRIC_NAME, desc),
083        snapshot.getMedian());
084    metricsRecordBuilder.addGauge(Interns.info(name + SEVENTY_FIFTH_PERCENTILE_METRIC_NAME, desc),
085        snapshot.get75thPercentile());
086    metricsRecordBuilder.addGauge(Interns.info(name + NINETIETH_PERCENTILE_METRIC_NAME, desc),
087        snapshot.get90thPercentile());
088    metricsRecordBuilder.addGauge(Interns.info(name + NINETY_FIFTH_PERCENTILE_METRIC_NAME, desc),
089        snapshot.get95thPercentile());
090    metricsRecordBuilder.addGauge(Interns.info(name + NINETY_EIGHTH_PERCENTILE_METRIC_NAME, desc),
091        snapshot.get98thPercentile());
092    metricsRecordBuilder.addGauge(Interns.info(name + NINETY_NINETH_PERCENTILE_METRIC_NAME, desc),
093        snapshot.get99thPercentile());
094    metricsRecordBuilder.addGauge(
095        Interns.info(name + NINETY_NINE_POINT_NINETH_PERCENTILE_METRIC_NAME, desc),
096        snapshot.get999thPercentile());
097  }
098}