| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| |
| package org.apache.samza.system.kinesis.metrics; |
| |
| import java.util.Arrays; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.function.Function; |
| import java.util.stream.Collectors; |
| |
| import org.apache.samza.metrics.Gauge; |
| import org.apache.samza.metrics.MetricsRegistry; |
| |
| import com.codahale.metrics.ExponentiallyDecayingReservoir; |
| import com.codahale.metrics.Histogram; |
| import com.codahale.metrics.Snapshot; |
| |
| |
| class SamzaHistogram { |
| |
| private static final List<Double> DEFAULT_HISTOGRAM_PERCENTILES = Arrays.asList(50D, 99D); |
| private final MetricsRegistry registry; |
| private final Histogram histogram; |
| private final List<Double> percentiles; |
| private final Map<Double, Gauge<Double>> gauges; |
| |
| SamzaHistogram(MetricsRegistry registry, String group, String name) { |
| this(registry, group, name, DEFAULT_HISTOGRAM_PERCENTILES); |
| } |
| |
| SamzaHistogram(MetricsRegistry registry, String group, String name, List<Double> percentiles) { |
| this.registry = registry; |
| this.histogram = new Histogram(new ExponentiallyDecayingReservoir()); |
| this.percentiles = percentiles; |
| this.gauges = percentiles.stream() |
| .filter(x -> x > 0 && x <= 100) |
| .collect( |
| Collectors.toMap(Function.identity(), x -> this.registry.newGauge(group, name + "_" + String.valueOf(0), 0D))); |
| } |
| |
| synchronized void update(long value) { |
| histogram.update(value); |
| Snapshot values = histogram.getSnapshot(); |
| percentiles.forEach(x -> gauges.get(x).set(values.getValue(x / 100))); |
| } |
| } |