content: /**
   * 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.activemq.store.kahadb.disk.journal;
  
  import org.apache.activemq.management.TimeStatisticImpl;
  import org.apache.activemq.store.kahadb.KahaDBStore;
  import org.apache.activemq.util.ByteSequence;
  import org.apache.activemq.util.Wait;
  import org.junit.Test;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.File;
  import java.util.Random;
  
  import static org.junit.Assert.assertTrue;
  
  public class PreallocationJournalLatencyTest {
  
      private static final Logger LOG = LoggerFactory.getLogger(PreallocationJournalLatencyTest.class);
      final Random rand = new Random();
  
      @Test
      public void preallocationLatency() throws Exception {
  
          TimeStatisticImpl sparse = executeTest(Journal.PreallocationStrategy.SPARSE_FILE.name());
          TimeStatisticImpl chunked_zeros = executeTest(Journal.PreallocationStrategy.CHUNKED_ZEROS.name());
          //TimeStatisticImpl zeros = executeTest(Journal.PreallocationStrategy.ZEROS.name());
          TimeStatisticImpl kernel = executeTest(Journal.PreallocationStrategy.OS_KERNEL_COPY.name());
  
          LOG.info("  sparse: " + sparse);
          LOG.info(" chunked: " + chunked_zeros);
          //LOG.info("   zeros: " + zeros);
          LOG.info("  kernel: " + kernel);
  
      }
  
      private TimeStatisticImpl executeTest(String preallocationStrategy)throws Exception {
          int randInt = rand.nextInt(100);
          File dataDirectory = new File("./target/activemq-data/kahadb" + randInt);
  
          final KahaDBStore store = new KahaDBStore();
          store.setCheckpointInterval(5000);
          store.setJournalMaxFileLength(32*1204*1024);
          store.deleteAllMessages();
          store.setDirectory(dataDirectory);
          store.setPreallocationStrategy(preallocationStrategy);
          store.setPreallocationScope(Journal.PreallocationScope.ENTIRE_JOURNAL_ASYNC.name());
          store.start();
  
          final File journalLog = new File(dataDirectory, "db-1.log");
          assertTrue("file exists", Wait.waitFor(new Wait.Condition() {
              @Override
              public boolean isSatisified() throws Exception {
                  return journalLog.exists();
              }
          }));
  
          final Journal journal = store.getJournal();
          ByteSequence byteSequence = new ByteSequence(new byte[16*1024]);
  
          TimeStatisticImpl timeStatistic = new TimeStatisticImpl("append", "duration");
          for (int i=0;i<5000; i++) {
              final long start = System.currentTimeMillis();
              journal.write(byteSequence, true);
              timeStatistic.addTime(System.currentTimeMillis() - start);
          }
          LOG.info("current journal dataFile id: " + journal.getCurrentDataFileId());
          store.stop();
          return timeStatistic;
      }
  
  }
  