Source code

001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019package org.apache.reef.runtime.common.driver.evaluator;
020
021import org.apache.commons.lang3.Validate;
022import org.apache.reef.annotations.audience.Private;
023import org.apache.reef.runtime.common.driver.parameters.EvaluatorIdlenessThreadPoolSize;
024import org.apache.reef.runtime.common.driver.parameters.EvaluatorIdlenessWaitInMilliseconds;
025import org.apache.reef.tang.annotations.Parameter;
026import org.apache.reef.wake.impl.DefaultThreadFactory;
027
028import javax.inject.Inject;
029import java.util.concurrent.ExecutorService;
030import java.util.concurrent.Executors;
031import java.util.logging.Level;
032import java.util.logging.Logger;
033
034/**
035 * Runs threads in a thread pool to check the completion of Evaluators on the closing
036 * of an {@link EvaluatorManager} in order to trigger Evaluator idleness checks.
037 */
038@Private
039public final class EvaluatorIdlenessThreadPool {
040  private static final Logger LOG = Logger.getLogger(EvaluatorIdlenessThreadPool.class.getName());
041
042  private final ExecutorService executor;
043  private final long waitInMillis;
044
045  @Inject
046  private EvaluatorIdlenessThreadPool(@Parameter(EvaluatorIdlenessThreadPoolSize.class) final int numThreads,
047                                      @Parameter(EvaluatorIdlenessWaitInMilliseconds.class) final long waitInMillis) {
048
049    Validate.isTrue(waitInMillis >= 0, "EvaluatorIdlenessWaitInMilliseconds must be configured to be >= 0");
050    Validate.isTrue(numThreads > 0, "EvaluatorIdlenessThreadPoolSize must be configured to be > 0");
051
052    this.waitInMillis = waitInMillis;
053    this.executor = Executors.newFixedThreadPool(
054        numThreads, new DefaultThreadFactory(EvaluatorIdlenessThreadPool.class.getName()));
055  }
056
057  /**
058   * Runs a check in the ThreadPool for the {@link EvaluatorManager} to wait for it to finish its
059   * Event Handling and check its idleness source.
060   * @param manager the {@link EvaluatorManager}
061   */
062  void runCheckAsync(final EvaluatorManager manager) {
063    executor.submit(new Runnable() {
064      @Override
065      public void run() {
066        while (!manager.isClosed()) {
067          try {
068            Thread.sleep(waitInMillis);
069          } catch (final InterruptedException e) {
070            LOG.log(Level.SEVERE, "Thread interrupted while waiting for Evaluator to finish.");
071            throw new RuntimeException(e);
072          }
073        }
074
075        manager.checkIdlenessSource();
076        LOG.log(Level.FINE, "Evaluator " + manager.getId() + " has finished.");
077      }
078    });
079  }
080}