org.apache.reef.runtime.common.driver.evaluator.EvaluatorIdlenessThreadPool.java Source code

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Here is the source code for org.apache.reef.runtime.common.driver.evaluator.EvaluatorIdlenessThreadPool.java

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/*
 * 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.reef.runtime.common.driver.evaluator;

import org.apache.commons.lang3.Validate;
import org.apache.reef.annotations.audience.Private;
import org.apache.reef.runtime.common.driver.parameters.EvaluatorIdlenessThreadPoolSize;
import org.apache.reef.runtime.common.driver.parameters.EvaluatorIdlenessWaitInMilliseconds;
import org.apache.reef.tang.annotations.Parameter;
import org.apache.reef.wake.impl.DefaultThreadFactory;

import javax.inject.Inject;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * Runs threads in a thread pool to check the completion of Evaluators on the closing
 * of an {@link EvaluatorManager} in order to trigger Evaluator idleness checks.
 */
@Private
public final class EvaluatorIdlenessThreadPool implements AutoCloseable {

    private static final Logger LOG = Logger.getLogger(EvaluatorIdlenessThreadPool.class.getName());

    private final ExecutorService executor;
    private final long waitInMillis;

    @Inject
    private EvaluatorIdlenessThreadPool(@Parameter(EvaluatorIdlenessThreadPoolSize.class) final int numThreads,
            @Parameter(EvaluatorIdlenessWaitInMilliseconds.class) final long waitInMillis) {

        Validate.isTrue(waitInMillis >= 0, "EvaluatorIdlenessWaitInMilliseconds must be configured to be >= 0");
        Validate.isTrue(numThreads > 0, "EvaluatorIdlenessThreadPoolSize must be configured to be > 0");

        this.waitInMillis = waitInMillis;

        this.executor = Executors.newFixedThreadPool(numThreads,
                new DefaultThreadFactory(this.getClass().getSimpleName()));
    }

    /**
     * Runs a check in the ThreadPool for the {@link EvaluatorManager} to wait for it to finish its
     * Event Handling and check its idleness source.
     * @param manager the {@link EvaluatorManager}
     */
    void runCheckAsync(final EvaluatorManager manager) {

        final String evaluatorId = manager.getId();
        LOG.log(Level.FINEST, "Idle check for Evaluator: {0}", manager);

        this.executor.submit(new Runnable() {

            @Override
            public void run() {

                LOG.log(Level.FINEST, "Idle check for Evaluator {0} - begin", evaluatorId);

                while (!manager.isClosed()) {
                    try {

                        LOG.log(Level.FINEST, "Waiting for Evaluator {0} to close: Sleep for {1} ms",
                                new Object[] { evaluatorId, waitInMillis });

                        Thread.sleep(waitInMillis);

                    } catch (final InterruptedException e) {
                        LOG.log(Level.SEVERE, "Thread interrupted while waiting for Evaluator to finish.");
                        throw new RuntimeException(e);
                    }
                }

                manager.checkIdlenessSource();

                LOG.log(Level.FINEST, "Idle check for Evaluator {0} - end", evaluatorId);
            }

            @Override
            public String toString() {
                return "CheckIdle: " + evaluatorId;
            }
        });
    }

    /**
     * Shutdown the thread pool of idleness checkers.
     */
    @Override
    public void close() {

        LOG.log(Level.FINE, "EvaluatorIdlenessThreadPool shutdown: begin");

        this.executor.shutdown();

        boolean isTerminated = false;
        try {
            isTerminated = this.executor.awaitTermination(this.waitInMillis, TimeUnit.MILLISECONDS);
        } catch (final InterruptedException ex) {
            LOG.log(Level.WARNING, "EvaluatorIdlenessThreadPool shutdown: Interrupted", ex);
        }

        if (isTerminated) {
            LOG.log(Level.FINE, "EvaluatorIdlenessThreadPool shutdown: Terminated successfully");
        } else {
            final List<Runnable> pendingJobs = this.executor.shutdownNow();
            LOG.log(Level.SEVERE, "EvaluatorIdlenessThreadPool shutdown: {0} jobs after timeout",
                    pendingJobs.size());
            LOG.log(Level.FINE, "EvaluatorIdlenessThreadPool shutdown: pending jobs: {0}", pendingJobs);
        }
    }
}