Java tutorial
/** * 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.hadoop.hdfs; import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.atomic.AtomicInteger; import java.util.concurrent.atomic.AtomicLong; import junit.framework.TestCase; import org.junit.Test; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.hdfs.util.InjectionEvent; import org.apache.hadoop.util.InjectionEventI; import org.apache.hadoop.util.InjectionHandler; public class TestAutoEditRollWhenAvatarFailover extends AvatarSetupUtil { final static Log LOG = LogFactory.getLog(TestAutoEditRollWhenAvatarFailover.class); /** * Test if we can get block locations after killing primary avatar, * failing over to standby avatar (making it the new primary), * restarting a new standby avatar, killing the new primary avatar and * failing over to the restarted standby. * * Write logs for a while to make sure automatic rolling are triggered. */ @Test public void testDoubleFailOverWithAutomaticRoll() throws Exception { setUp(false, "testDoubleFailOverWithAutomaticRoll"); // To make sure it's never the case that both primary and standby // issue rolling, we use a injection handler. final AtomicBoolean startKeepThread = new AtomicBoolean(true); final AtomicInteger countAutoRolled = new AtomicInteger(0); final AtomicBoolean needFail = new AtomicBoolean(false); final AtomicLong currentThreadId = new AtomicLong(-1); final Object waitFor10Rolls = new Object(); InjectionHandler.set(new InjectionHandler() { @Override protected void _processEvent(InjectionEventI event, Object... args) { if (event == InjectionEvent.FSEDIT_AFTER_AUTOMATIC_ROLL) { countAutoRolled.incrementAndGet(); if (countAutoRolled.get() >= 10) { synchronized (waitFor10Rolls) { waitFor10Rolls.notifyAll(); } } if (!startKeepThread.get()) { currentThreadId.set(-1); } else if (currentThreadId.get() == -1) { currentThreadId.set(Thread.currentThread().getId()); } else if (currentThreadId.get() != Thread.currentThread().getId()) { LOG.warn("[Thread " + Thread.currentThread().getId() + "] expected: " + currentThreadId); needFail.set(true); } LOG.info("[Thread " + Thread.currentThread().getId() + "] finish automatic log rolling, count " + countAutoRolled.get()); // Increase the rolling time a little bit once after 7 auto rolls if (countAutoRolled.get() % 7 == 3) { DFSTestUtil.waitNMilliSecond(75); } } } }); FileSystem fs = cluster.getFileSystem(); // Add some transactions during a period of time before failing over. long startTime = System.currentTimeMillis(); for (int i = 0; i < 100; i++) { fs.setTimes(new Path("/"), 0, 0); DFSTestUtil.waitNMilliSecond(100); if (i % 10 == 0) { LOG.info("================== executed " + i + " queries"); } if (countAutoRolled.get() >= 10) { LOG.info("Automatic rolled 10 times."); long duration = System.currentTimeMillis() - startTime; TestCase.assertTrue("Automatic rolled 10 times in just " + duration + " msecs, which is too short", duration > 4500); break; } } TestCase.assertTrue("Only " + countAutoRolled + " automatic rolls triggered, which is lower than expected.", countAutoRolled.get() >= 10); // Tune the rolling timeout temporarily to avoid race conditions // only triggered in tests cluster.getPrimaryAvatar(0).avatar.namesystem.getFSImage().getEditLog().setTimeoutRollEdits(5000); cluster.getStandbyAvatar(0).avatar.namesystem.getFSImage().getEditLog().setTimeoutRollEdits(5000); LOG.info("================== killing primary 1"); cluster.killPrimary(); // Fail over and make sure after fail over, automatic edits roll still // will happen. countAutoRolled.set(0); startKeepThread.set(false); currentThreadId.set(-1); LOG.info("================== failing over 1"); cluster.failOver(); cluster.getPrimaryAvatar(0).avatar.namesystem.getFSImage().getEditLog().setTimeoutRollEdits(1000); LOG.info("================== restarting standby"); cluster.restartStandby(); cluster.getStandbyAvatar(0).avatar.namesystem.getFSImage().getEditLog().setTimeoutRollEdits(1000); LOG.info("================== Finish restarting standby"); // Wait for automatic rolling happens if there is no new transaction. startKeepThread.set(true); startTime = System.currentTimeMillis(); long waitDeadLine = startTime + 20000; synchronized (waitFor10Rolls) { while (System.currentTimeMillis() < waitDeadLine && countAutoRolled.get() < 10) { waitFor10Rolls.wait(waitDeadLine - System.currentTimeMillis()); } } TestCase.assertTrue("Only " + countAutoRolled + " automatic rolls triggered, which is lower than expected.", countAutoRolled.get() >= 10); long duration = System.currentTimeMillis() - startTime; TestCase.assertTrue("Automatic rolled 10 times in just " + duration + " msecs", duration > 9000); // failover back countAutoRolled.set(0); startKeepThread.set(false); currentThreadId.set(-1); cluster.getPrimaryAvatar(0).avatar.namesystem.getFSImage().getEditLog().setTimeoutRollEdits(6000); cluster.getStandbyAvatar(0).avatar.namesystem.getFSImage().getEditLog().setTimeoutRollEdits(6000); LOG.info("================== killing primary 2"); cluster.killPrimary(); LOG.info("================== failing over 2"); cluster.failOver(); cluster.getPrimaryAvatar(0).avatar.namesystem.getFSImage().getEditLog().setTimeoutRollEdits(1000); // Make sure after failover back, automatic rolling can still happen. startKeepThread.set(true); for (int i = 0; i < 100; i++) { fs.setTimes(new Path("/"), 0, 0); DFSTestUtil.waitNMilliSecond(200); if (i % 10 == 0) { LOG.info("================== executed " + i + " queries"); } if (countAutoRolled.get() > 10) { LOG.info("Automatic rolled 10 times."); duration = System.currentTimeMillis() - startTime; TestCase.assertTrue("Automatic rolled 10 times in just " + duration + " msecs, which is too short", duration > 9000); break; } } TestCase.assertTrue("Only " + countAutoRolled + " automatic rolls triggered, which is lower than expected.", countAutoRolled.get() >= 10); InjectionHandler.clear(); if (needFail.get()) { TestCase.fail("Automatic rolling doesn't happen in the same thread when should."); } } }