/**
* 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.hbase;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import java.io.IOException;
import java.util.Collection;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.logging.impl.Log4JLogger;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.regionserver.ConstantSizeRegionSplitPolicy;
import org.apache.hadoop.hbase.regionserver.HRegion;
import org.apache.hadoop.hbase.regionserver.HRegionServer;
import org.apache.hadoop.hbase.regionserver.HStore;
import org.apache.hadoop.hbase.regionserver.RegionServerServices;
import org.apache.hadoop.hbase.regionserver.Store;
import org.apache.hadoop.hbase.regionserver.StoreFile;
import org.apache.hadoop.hbase.regionserver.compactions.CompactionContext;
import org.apache.hadoop.hbase.regionserver.wal.HLog;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.JVMClusterUtil.RegionServerThread;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.server.datanode.DataNode;
import org.apache.hadoop.hdfs.server.namenode.FSNamesystem;
import org.apache.hadoop.hdfs.server.namenode.LeaseManager;
import org.apache.log4j.Level;
import org.junit.Test;
import org.junit.experimental.categories.Category;
/**
* Test for the case where a regionserver going down has enough cycles to do damage to regions
* that have actually been assigned elsehwere.
*
* <p>If we happen to assign a region before it fully done with in its old location -- i.e. it is on two servers at the
* same time -- all can work fine until the case where the region on the dying server decides to compact or otherwise
* change the region file set. The region in its new location will then get a surprise when it tries to do something
* w/ a file removed by the region in its old location on dying server.
*
* <p>Making a test for this case is a little tough in that even if a file is deleted up on the namenode,
* if the file was opened before the delete, it will continue to let reads happen until something changes the
* state of cached blocks in the dfsclient that was already open (a block from the deleted file is cleaned
* from the datanode by NN).
*
* <p>What we will do below is do an explicit check for existence on the files listed in the region that
* has had some files removed because of a compaction. This sort of hurry's along and makes certain what is a chance
* occurance.
*/
@Category(MediumTests.class)
public class TestIOFencing {
static final Log LOG = LogFactory.getLog(TestIOFencing.class);
static {
((Log4JLogger)FSNamesystem.LOG).getLogger().setLevel(Level.ALL);
((Log4JLogger)DataNode.LOG).getLogger().setLevel(Level.ALL);
((Log4JLogger)LeaseManager.LOG).getLogger().setLevel(Level.ALL);
((Log4JLogger)LogFactory.getLog("org.apache.hadoop.hdfs.server.namenode.FSNamesystem")).getLogger().setLevel(Level.ALL);
((Log4JLogger)DFSClient.LOG).getLogger().setLevel(Level.ALL);
((Log4JLogger)HLog.LOG).getLogger().setLevel(Level.ALL);
}
public abstract static class CompactionBlockerRegion extends HRegion {
volatile int compactCount = 0;
volatile CountDownLatch compactionsBlocked = new CountDownLatch(0);
volatile CountDownLatch compactionsWaiting = new CountDownLatch(0);
@SuppressWarnings("deprecation")
public CompactionBlockerRegion(Path tableDir, HLog log,
FileSystem fs, Configuration confParam, HRegionInfo info,
HTableDescriptor htd, RegionServerServices rsServices) {
super(tableDir, log, fs, confParam, info, htd, rsServices);
}
public void stopCompactions() {
compactionsBlocked = new CountDownLatch(1);
compactionsWaiting = new CountDownLatch(1);
}
public void allowCompactions() {
LOG.debug("allowing compactions");
compactionsBlocked.countDown();
}
public void waitForCompactionToBlock() throws IOException {
try {
LOG.debug("waiting for compaction to block");
compactionsWaiting.await();
LOG.debug("compaction block reached");
} catch (InterruptedException ex) {
throw new IOException(ex);
}
}
@Override
public boolean compact(CompactionContext compaction, Store store) throws IOException {
try {
return super.compact(compaction, store);
} finally {
compactCount++;
}
}
public int countStoreFiles() {
int count = 0;
for (Store store : stores.values()) {
count += store.getStorefilesCount();
}
return count;
}
}
/**
* An override of HRegion that allows us park compactions in a holding pattern and
* then when appropriate for the test, allow them proceed again.
*/
public static class BlockCompactionsInPrepRegion extends CompactionBlockerRegion {
public BlockCompactionsInPrepRegion(Path tableDir, HLog log,
FileSystem fs, Configuration confParam, HRegionInfo info,
HTableDescriptor htd, RegionServerServices rsServices) {
super(tableDir, log, fs, confParam, info, htd, rsServices);
}
@Override
protected void doRegionCompactionPrep() throws IOException {
compactionsWaiting.countDown();
try {
compactionsBlocked.await();
} catch (InterruptedException ex) {
throw new IOException();
}
super.doRegionCompactionPrep();
}
}
/**
* An override of HRegion that allows us park compactions in a holding pattern and
* then when appropriate for the test, allow them proceed again. This allows the compaction
* entry to go the WAL before blocking, but blocks afterwards
*/
public static class BlockCompactionsInCompletionRegion extends CompactionBlockerRegion {
public BlockCompactionsInCompletionRegion(Path tableDir, HLog log,
FileSystem fs, Configuration confParam, HRegionInfo info,
HTableDescriptor htd, RegionServerServices rsServices) {
super(tableDir, log, fs, confParam, info, htd, rsServices);
}
@Override
protected HStore instantiateHStore(final HColumnDescriptor family) throws IOException {
return new BlockCompactionsInCompletionHStore(this, family, this.conf);
}
}
public static class BlockCompactionsInCompletionHStore extends HStore {
CompactionBlockerRegion r;
protected BlockCompactionsInCompletionHStore(HRegion region, HColumnDescriptor family,
Configuration confParam) throws IOException {
super(region, family, confParam);
r = (CompactionBlockerRegion) region;
}
@Override
protected void completeCompaction(Collection<StoreFile> compactedFiles) throws IOException {
try {
r.compactionsWaiting.countDown();
r.compactionsBlocked.await();
} catch (InterruptedException ex) {
throw new IOException(ex);
}
super.completeCompaction(compactedFiles);
}
}
private final static HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
private final static TableName TABLE_NAME =
TableName.valueOf("tabletest");
private final static byte[] FAMILY = Bytes.toBytes("family");
private static final int FIRST_BATCH_COUNT = 4000;
private static final int SECOND_BATCH_COUNT = FIRST_BATCH_COUNT;
/**
* Test that puts up a regionserver, starts a compaction on a loaded region but holds the
* compaction until after we have killed the server and the region has come up on
* a new regionserver altogether. This fakes the double assignment case where region in one
* location changes the files out from underneath a region being served elsewhere.
*/
@Test
public void testFencingAroundCompaction() throws Exception {
doTest(BlockCompactionsInPrepRegion.class);
}
/**
* Test that puts up a regionserver, starts a compaction on a loaded region but holds the
* compaction completion until after we have killed the server and the region has come up on
* a new regionserver altogether. This fakes the double assignment case where region in one
* location changes the files out from underneath a region being served elsewhere.
*/
@Test
public void testFencingAroundCompactionAfterWALSync() throws Exception {
doTest(BlockCompactionsInCompletionRegion.class);
}
public void doTest(Class<?> regionClass) throws Exception {
Configuration c = TEST_UTIL.getConfiguration();
c.setBoolean(HConstants.DISTRIBUTED_LOG_REPLAY_KEY, false);
// Insert our custom region
c.setClass(HConstants.REGION_IMPL, regionClass, HRegion.class);
c.setBoolean("dfs.support.append", true);
// Encourage plenty of flushes
c.setLong("hbase.hregion.memstore.flush.size", 200000);
c.set(HConstants.HBASE_REGION_SPLIT_POLICY_KEY, ConstantSizeRegionSplitPolicy.class.getName());
// Only run compaction when we tell it to
c.setInt("hbase.hstore.compactionThreshold", 1000);
c.setLong("hbase.hstore.blockingStoreFiles", 1000);
// Compact quickly after we tell it to!
c.setInt("hbase.regionserver.thread.splitcompactcheckfrequency", 1000);
LOG.info("Starting mini cluster");
TEST_UTIL.startMiniCluster(1);
CompactionBlockerRegion compactingRegion = null;
HBaseAdmin admin = null;
try {
LOG.info("Creating admin");
admin = new HBaseAdmin(c);
LOG.info("Creating table");
TEST_UTIL.createTable(TABLE_NAME, FAMILY);
HTable table = new HTable(c, TABLE_NAME);
LOG.info("Loading test table");
// Find the region
List<HRegion> testRegions = TEST_UTIL.getMiniHBaseCluster().findRegionsForTable(TABLE_NAME);
assertEquals(1, testRegions.size());
compactingRegion = (CompactionBlockerRegion)testRegions.get(0);
LOG.info("Blocking compactions");
compactingRegion.stopCompactions();
long lastFlushTime = compactingRegion.getLastFlushTime();
// Load some rows
TEST_UTIL.loadNumericRows(table, FAMILY, 0, FIRST_BATCH_COUNT);
// Wait till flush has happened, otherwise there won't be multiple store files
long startWaitTime = System.currentTimeMillis();
while (compactingRegion.getLastFlushTime() <= lastFlushTime) {
LOG.info("Waiting for the region to flush " + compactingRegion.getRegionNameAsString());
Thread.sleep(1000);
assertTrue("Timed out waiting for the region to flush",
System.currentTimeMillis() - startWaitTime < 30000);
}
assertTrue(compactingRegion.countStoreFiles() > 1);
final byte REGION_NAME[] = compactingRegion.getRegionName();
LOG.info("Asking for compaction");
admin.majorCompact(TABLE_NAME.getName());
LOG.info("Waiting for compaction to be about to start");
compactingRegion.waitForCompactionToBlock();
LOG.info("Starting a new server");
RegionServerThread newServerThread = TEST_UTIL.getMiniHBaseCluster().startRegionServer();
HRegionServer newServer = newServerThread.getRegionServer();
LOG.info("Killing region server ZK lease");
TEST_UTIL.expireRegionServerSession(0);
CompactionBlockerRegion newRegion = null;
startWaitTime = System.currentTimeMillis();
while (newRegion == null) {
LOG.info("Waiting for the new server to pick up the region " + Bytes.toString(REGION_NAME));
Thread.sleep(1000);
newRegion = (CompactionBlockerRegion)newServer.getOnlineRegion(REGION_NAME);
assertTrue("Timed out waiting for new server to open region",
System.currentTimeMillis() - startWaitTime < 300000);
}
LOG.info("Allowing compaction to proceed");
compactingRegion.allowCompactions();
while (compactingRegion.compactCount == 0) {
Thread.sleep(1000);
}
// The server we killed stays up until the compaction that was started before it was killed completes. In logs
// you should see the old regionserver now going down.
LOG.info("Compaction finished");
// After compaction of old region finishes on the server that was going down, make sure that
// all the files we expect are still working when region is up in new location.
FileSystem fs = newRegion.getFilesystem();
for (String f: newRegion.getStoreFileList(new byte [][] {FAMILY})) {
assertTrue("After compaction, does not exist: " + f, fs.exists(new Path(f)));
}
// If we survive the split keep going...
// Now we make sure that the region isn't totally confused. Load up more rows.
TEST_UTIL.loadNumericRows(table, FAMILY, FIRST_BATCH_COUNT, FIRST_BATCH_COUNT + SECOND_BATCH_COUNT);
admin.majorCompact(TABLE_NAME.getName());
startWaitTime = System.currentTimeMillis();
while (newRegion.compactCount == 0) {
Thread.sleep(1000);
assertTrue("New region never compacted", System.currentTimeMillis() - startWaitTime < 180000);
}
assertEquals(FIRST_BATCH_COUNT + SECOND_BATCH_COUNT, TEST_UTIL.countRows(table));
} finally {
if (compactingRegion != null) {
compactingRegion.allowCompactions();
}
admin.close();
TEST_UTIL.shutdownMiniCluster();
}
}
}