| /* |
| * 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.jackrabbit.oak.commons.benchmark; |
| |
| import java.util.concurrent.TimeUnit; |
| |
| import org.apache.commons.math3.stat.descriptive.DescriptiveStatistics; |
| |
| |
| /** |
| * Poor man's micro benchmark suite. |
| * <p> |
| * Implementations of {@link Benchmark} are executed by the {@link #run(Benchmark)} method. |
| * Execution consists of a warm up phase followed by the actual benchmark run. |
| */ |
| public final class MicroBenchmark { |
| private MicroBenchmark() { } |
| |
| /** |
| * Benchmark base class. |
| */ |
| public abstract static class Benchmark { |
| |
| /** |
| * The benchmark runner calls this method first and exactly once by for setting up |
| * the test fixture. |
| */ |
| public void setup() throws Exception { } |
| |
| /** |
| * The benchmark runner calls the method before every call to the {@code run} |
| * method for setting the scope of the subsequent call to {@code run}. |
| */ |
| public void beforeRun() throws Exception { } |
| |
| /** |
| * The benchmark runner calls this method a number of times to measure its |
| * runtime performance. |
| */ |
| public abstract void run() throws Exception; |
| |
| /** |
| * The benchmark runner calls the method after every call to the {@code run} |
| * method for tearing down the scope of the previous call to {@code run}. |
| */ |
| public void afterRun() throws Exception { } |
| |
| /** |
| * The benchmark runner calls this method exactly once and only if the benchmark |
| * did not result in an error. This default implementation tabulates |
| * the percentiles of the gathered test statistics. |
| */ |
| public void result(DescriptiveStatistics statistics) { |
| System.out.println(this); |
| if (statistics.getN() > 0) { |
| System.out.format( |
| "%6s %6s %6s %6s %6s %6s %6s %6s%n", |
| "min", "10%", "50%", "90%", "max", "mean", "stdev", "N"); |
| System.out.format( |
| "%6.0f %6.0f %6.0f %6.0f %6.0f %6.0f %6.0f %6d%n", |
| statistics.getMin() / 1000000, |
| statistics.getPercentile(10.0) / 1000000, |
| statistics.getPercentile(50.0) / 1000000, |
| statistics.getPercentile(90.0) / 1000000, |
| statistics.getMax() / 1000000, |
| statistics.getMean() / 1000000, |
| statistics.getStandardDeviation() / 1000000, |
| statistics.getN()); |
| } else { |
| System.out.println("No results"); |
| } |
| } |
| |
| /** |
| * The benchmark runner calls this method last and exactly once for tearing down |
| * the test fixture. |
| */ |
| public void tearDown() throws Exception { } |
| } |
| |
| /** |
| * Run a {@code benchmark} |
| * @param benchmark |
| * @throws Exception |
| */ |
| public static void run(Benchmark benchmark) throws Exception { |
| benchmark.setup(); |
| try { |
| // Warm up |
| runTest(benchmark); |
| |
| // Run the test |
| benchmark.result(runTest(benchmark)); |
| } finally { |
| benchmark.tearDown(); |
| } |
| } |
| |
| private static DescriptiveStatistics runTest(Benchmark benchmark) throws Exception { |
| final DescriptiveStatistics statistics = new DescriptiveStatistics(); |
| long runtimeEnd = System.currentTimeMillis() + TimeUnit.SECONDS.toMillis(60); |
| while (System.currentTimeMillis() < runtimeEnd) { |
| statistics.addValue(execute(benchmark)); |
| } |
| return statistics; |
| } |
| |
| private static double execute(Benchmark benchmark) throws Exception { |
| benchmark.beforeRun(); |
| try { |
| long start = System.nanoTime(); |
| benchmark.run(); |
| return System.nanoTime() - start; |
| } finally { |
| benchmark.afterRun(); |
| } |
| } |
| |
| } |