com.github.benmanes.caffeine.cache.Stresser.java Source code

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Here is the source code for com.github.benmanes.caffeine.cache.Stresser.java

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/*
 * Copyright 2014 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.caffeine.cache;

import static java.util.concurrent.TimeUnit.SECONDS;

import java.time.LocalTime;
import java.util.Arrays;
import java.util.concurrent.Executors;
import java.util.concurrent.ForkJoinPool;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;

import org.apache.commons.lang3.StringUtils;

import com.github.benmanes.caffeine.testing.ConcurrentTestHarness;
import com.google.common.base.Stopwatch;
import com.google.common.util.concurrent.ThreadFactoryBuilder;

/**
 * A stress test to observe if the cache is able to drain the buffers fast enough under a synthetic
 * load.
 *
 * @author ben.manes@gmail.com (Ben Manes)
 */
public final class Stresser {
    private static final String[] STATUS = { "Idle", "Required", "Processing -> Idle", "Processing -> Required" };
    private static final int MAX_THREADS = 2 * Runtime.getRuntime().availableProcessors();
    private static final int WRITE_MAX_SIZE = (1 << 12);
    private static final int TOTAL_KEYS = (1 << 20);
    private static final int MASK = TOTAL_KEYS - 1;
    private static final int STATUS_INTERVAL = 5;

    private final BoundedLocalCache<Integer, Integer> local;
    private final LoadingCache<Integer, Integer> cache;
    private final Stopwatch stopwatch;
    private final Integer[] ints;

    private enum Operation {
        READ(MAX_THREADS, TOTAL_KEYS), WRITE(MAX_THREADS, WRITE_MAX_SIZE), REFRESH(1, WRITE_MAX_SIZE);

        private final int maxThreads;
        private final int maxEntries;

        private Operation(int maxThreads, int maxEntries) {
            this.maxThreads = maxThreads;
            this.maxEntries = maxEntries;
        }
    }

    private static final Operation operation = Operation.REFRESH;

    public Stresser() {
        ThreadFactory threadFactory = new ThreadFactoryBuilder().setPriority(Thread.MAX_PRIORITY).setDaemon(true)
                .build();
        Executors.newSingleThreadScheduledExecutor(threadFactory).scheduleAtFixedRate(this::status, STATUS_INTERVAL,
                STATUS_INTERVAL, SECONDS);
        cache = Caffeine.newBuilder().maximumSize(operation.maxEntries).recordStats().build(key -> key);
        local = (BoundedLocalCache<Integer, Integer>) cache.asMap();
        ints = new Integer[TOTAL_KEYS];
        Arrays.setAll(ints, key -> {
            cache.put(key, key);
            return key;
        });
        cache.cleanUp();
        stopwatch = Stopwatch.createStarted();
        status();
    }

    public void run() throws InterruptedException {
        ConcurrentTestHarness.timeTasks(operation.maxThreads, () -> {
            int index = ThreadLocalRandom.current().nextInt();
            for (;;) {
                Integer key = ints[index++ & MASK];
                switch (operation) {
                case READ:
                    cache.getIfPresent(key);
                    break;
                case WRITE:
                    cache.put(key, key);
                    break;
                case REFRESH:
                    cache.refresh(key);
                    break;
                }
            }
        });
    }

    private void status() {
        local.evictionLock.lock();
        int pendingWrites = local.writeBuffer().size();
        int drainStatus = local.drainStatus();
        local.evictionLock.unlock();

        LocalTime elapsedTime = LocalTime.ofSecondOfDay(stopwatch.elapsed(TimeUnit.SECONDS));
        System.out.printf("---------- %s ----------%n", elapsedTime);
        System.out.printf("Pending reads: %,d; writes: %,d%n", local.readBuffer.size(), pendingWrites);
        System.out.printf("Drain status = %s (%s)%n", STATUS[drainStatus], drainStatus);
        System.out.printf("Evictions = %,d%n", cache.stats().evictionCount());
        System.out.printf("Size = %,d (max: %,d)%n", local.data.mappingCount(), operation.maxEntries);
        System.out.printf("Lock = [%s%n", StringUtils.substringAfter(local.evictionLock.toString(), "["));
        System.out.printf("Pending tasks = %,d%n", ForkJoinPool.commonPool().getQueuedSubmissionCount());

        long maxMemory = Runtime.getRuntime().maxMemory();
        long freeMemory = Runtime.getRuntime().freeMemory();
        long allocatedMemory = Runtime.getRuntime().totalMemory();
        System.out.printf("Max Memory = %,d bytes%n", maxMemory);
        System.out.printf("Free Memory = %,d bytes%n", freeMemory);
        System.out.printf("Allocated Memory = %,d bytes%n", allocatedMemory);

        System.out.println();
    }

    public static void main(String[] args) throws Exception {
        new Stresser().run();
    }
}