com.github.benmanes.multiway.EliminationProfile.java Source code

Introduction

Here is the source code for com.github.benmanes.multiway.EliminationProfile.java

Source

/*
 * Copyright 2013 Ben Manes. All Rights Reserved.
 *
 * 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.github.benmanes.multiway;

import java.util.concurrent.Executors;
import java.util.concurrent.LinkedTransferQueue;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TransferQueue;

import com.google.common.base.Stopwatch;
import com.twitter.jsr166e.LongAdder;

/**
 * A simple bootstrap for inspecting with an attached profiler.
 *
 * @author Ben Manes (ben.manes@gmail.com)
 */
public final class EliminationProfile {
    static final int DISPLAY_DELAY_SEC = 5;
    static final Integer ELEMENT = 1;

    final LongAdder calls;
    final Runnable runner;

    EliminationProfile() {
        calls = new LongAdder();

        // The task to profile
        runner = newEliminationStackRunner();
        //runner = newLinkedTransferQueueRunner();
    }

    void run() throws Exception {
        ConcurrentTestHarness.timeTasks(25, runner);
    }

    Runnable newEliminationStackRunner() {
        final EliminationStack<Integer> stack = new EliminationStack<>();
        return new Runnable() {
            @Override
            public void run() {
                final ThreadLocalRandom random = ThreadLocalRandom.current();
                for (;;) {
                    if (random.nextBoolean()) {
                        stack.push(ELEMENT);
                    } else {
                        stack.pop();
                    }
                    calls.increment();
                }
            }
        };
    }

    Runnable newLinkedTransferQueueRunner() {
        final TransferQueue<Integer> queue = new LinkedTransferQueue<>();
        return new Runnable() {
            @Override
            public void run() {
                final ThreadLocalRandom random = ThreadLocalRandom.current();
                for (;;) {
                    if (random.nextBoolean()) {
                        queue.offer(ELEMENT);
                    } else {
                        queue.poll();
                    }
                    calls.increment();
                }
            }
        };
    }

    void scheduleStatusTask() {
        Executors.newSingleThreadScheduledExecutor().scheduleWithFixedDelay(new Runnable() {
            final Stopwatch stopwatch = new Stopwatch().start();

            @Override
            public void run() {
                long count = calls.longValue();
                long rate = count / stopwatch.elapsed(TimeUnit.SECONDS);
                System.out.printf("%s - %,d [%,d / sec]\n", stopwatch, count, rate);
            }
        }, DISPLAY_DELAY_SEC, DISPLAY_DELAY_SEC, TimeUnit.SECONDS);
    }

    public static void main(String[] args) throws Exception {
        EliminationProfile profile = new EliminationProfile();
        profile.scheduleStatusTask();
        profile.run();
    }
}