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, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.hadoop.hbase.chaos.actions;
020
021import java.io.IOException;
022
023import org.apache.hadoop.hbase.ServerName;
024import org.apache.hadoop.hbase.chaos.monkies.PolicyBasedChaosMonkey;
025import org.slf4j.Logger;
026import org.slf4j.LoggerFactory;
027
028/**
029 * Action that adds high cpu load to a random regionserver for a given duration
030 */
031public class AddCPULoadAction extends SudoCommandAction {
032  protected static final Logger LOG = LoggerFactory.getLogger(AddCPULoadAction.class);
033  private static final String CPU_LOAD_COMMAND =
034      "seq 1 %s | xargs -I{} -n 1 -P %s timeout %s dd if=/dev/urandom of=/dev/null bs=1M " +
035          "iflag=fullblock";
036
037  private final long duration;
038  private long processes;
039
040  /**
041   * Add high load to cpu
042   *
043   * @param duration  Duration that this thread should generate the load for in milliseconds
044   * @param processes The number of parallel processes, should be equal to cpu threads for max load
045   */
046  public AddCPULoadAction(long duration, long processes, long timeout) {
047    super(timeout);
048    this.duration = duration;
049    this.processes = processes;
050  }
051
052  protected void localPerform() throws IOException {
053    LOG.info("Starting to execute AddCPULoadAction");
054    ServerName server = PolicyBasedChaosMonkey.selectRandomItem(getCurrentServers());
055    String hostname = server.getHostname();
056
057    try {
058      clusterManager.execSudo(hostname, timeout, getCommand());
059    } catch (IOException ex){
060      //This will always happen. We use timeout to kill a continously running process
061      //after the duration expires
062    }
063    LOG.info("Finished to execute AddCPULoadAction");
064  }
065
066  private String getCommand(){
067    return String.format(CPU_LOAD_COMMAND, processes, processes, duration/1000f);
068  }
069}