| /* |
| * Copyright (C) 2014 The Guava Authors |
| * |
| * Licensed 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 com.google.common.util.concurrent; |
| |
| import static com.google.common.util.concurrent.MoreExecutors.directExecutor; |
| import static com.google.common.util.concurrent.MoreExecutors.newDirectExecutorService; |
| |
| import com.google.caliper.AfterExperiment; |
| import com.google.caliper.BeforeExperiment; |
| import com.google.caliper.Benchmark; |
| import com.google.caliper.Param; |
| import com.google.caliper.api.Footprint; |
| import com.google.caliper.api.VmOptions; |
| |
| import java.util.HashSet; |
| import java.util.Set; |
| import java.util.concurrent.Executor; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| /** |
| * A benchmark comparing the {@link MoreExecutors#newDirectExecutorService()} to |
| * {@link MoreExecutors#directExecutor}. |
| */ |
| @VmOptions({"-Xms12g", "-Xmx12g", "-d64"}) |
| public class MoreExecutorsDirectExecutorBenchmark { |
| enum Impl { |
| EXECUTOR_SERVICE { |
| @Override Executor executor() { |
| return newDirectExecutorService(); |
| } |
| }, |
| EXECUTOR { |
| @Override Executor executor() { |
| return directExecutor(); |
| } |
| }; |
| abstract Executor executor(); |
| } |
| |
| @Param Impl impl; |
| Executor executor; |
| |
| static final class CountingRunnable implements Runnable { |
| AtomicInteger integer = new AtomicInteger(); |
| @Override public void run() { |
| integer.incrementAndGet(); |
| } |
| } |
| |
| CountingRunnable countingRunnable = new CountingRunnable(); |
| |
| Set<Thread> threads = new HashSet<Thread>(); |
| |
| @BeforeExperiment void before() { |
| executor = impl.executor(); |
| for (int i = 0; i < 4; i++) { |
| Thread thread = new Thread() { |
| @Override public void run() { |
| CountingRunnable localRunnable = new CountingRunnable(); |
| while (!isInterrupted()) { |
| executor.execute(localRunnable); |
| } |
| countingRunnable.integer.addAndGet(localRunnable.integer.get()); |
| } |
| }; |
| threads.add(thread); |
| } |
| } |
| |
| @AfterExperiment void after() { |
| for (Thread thread : threads) { |
| thread.interrupt(); // try to get them to exit |
| } |
| threads.clear(); |
| } |
| |
| @Footprint Object measureSize() { |
| return executor; |
| } |
| |
| @Benchmark int timeUncontendedExecute(int reps) { |
| final Executor executor = this.executor; |
| final CountingRunnable countingRunnable = this.countingRunnable; |
| for (int i = 0; i < reps; i++) { |
| executor.execute(countingRunnable); |
| } |
| return countingRunnable.integer.get(); |
| } |
| |
| @Benchmark int timeContendedExecute(int reps) { |
| final Executor executor = this.executor; |
| for (Thread thread : threads) { |
| if (!thread.isAlive()) { |
| thread.start(); |
| } |
| } |
| final CountingRunnable countingRunnable = this.countingRunnable; |
| for (int i = 0; i < reps; i++) { |
| executor.execute(countingRunnable); |
| } |
| return countingRunnable.integer.get(); |
| } |
| } |