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.hbase.regionserver.wal; import static org.junit.Assert.assertTrue; import static org.junit.Assert.assertFalse; import java.util.List; import java.util.ArrayList; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.fs.Path; import org.apache.hadoop.hbase.HBaseTestingUtility; import org.apache.hadoop.hbase.HColumnDescriptor; import org.apache.hadoop.hbase.HRegionInfo; import org.apache.hadoop.hbase.HTableDescriptor; import org.apache.hadoop.hbase.MediumTests; import org.apache.hadoop.hbase.TableName; import org.apache.hadoop.hbase.client.HTable; import org.apache.hadoop.hbase.client.Put; import org.apache.hadoop.hbase.regionserver.HRegionServer; import org.apache.hadoop.hbase.regionserver.wal.HLog; import org.apache.hadoop.hbase.util.Bytes; import org.apache.hadoop.hbase.util.FSUtils; import org.apache.hadoop.hdfs.MiniDFSCluster; import org.junit.AfterClass; import org.junit.BeforeClass; import org.junit.Test; import org.junit.experimental.categories.Category; /** * Tests that verifies that the log is forced to be rolled every "hbase.regionserver.logroll.period" */ @Category(MediumTests.class) public class TestLogRollPeriod { private static final Log LOG = LogFactory.getLog(TestLogRolling.class); private final static HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility(); private final static long LOG_ROLL_PERIOD = 4000; @BeforeClass public static void setUpBeforeClass() throws Exception { // disable the ui TEST_UTIL.getConfiguration().setInt("hbase.regionsever.info.port", -1); TEST_UTIL.getConfiguration().setLong("hbase.regionserver.logroll.period", LOG_ROLL_PERIOD); TEST_UTIL.startMiniCluster(); } @AfterClass public static void tearDownAfterClass() throws Exception { TEST_UTIL.shutdownMiniCluster(); } /** * Tests that the LogRoller perform the roll even if there are no edits */ @Test public void testNoEdits() throws Exception { final String tableName = "TestLogRollPeriodNoEdits"; TEST_UTIL.createTable(tableName, "cf"); try { HTable table = new HTable(TEST_UTIL.getConfiguration(), tableName); try { HRegionServer server = TEST_UTIL.getRSForFirstRegionInTable(Bytes.toBytes(tableName)); HLog log = server.getWAL(); checkMinLogRolls(log, 5); } finally { table.close(); } } finally { TEST_UTIL.deleteTable(tableName); } } /** * Tests that the LogRoller perform the roll with some data in the log */ @Test(timeout = 60000) public void testWithEdits() throws Exception { final String tableName = "TestLogRollPeriodWithEdits"; final String family = "cf"; TEST_UTIL.createTable(tableName, family); try { HRegionServer server = TEST_UTIL.getRSForFirstRegionInTable(Bytes.toBytes(tableName)); HLog log = server.getWAL(); final HTable table = new HTable(TEST_UTIL.getConfiguration(), tableName); Thread writerThread = new Thread("writer") { @Override public void run() { try { long row = 0; while (!interrupted()) { Put p = new Put(Bytes.toBytes(String.format("row%d", row))); p.add(Bytes.toBytes(family), Bytes.toBytes("col"), Bytes.toBytes(row)); table.put(p); row++; Thread.sleep(LOG_ROLL_PERIOD / 16); } } catch (Exception e) { LOG.warn(e); } } }; try { writerThread.start(); checkMinLogRolls(log, 5); } finally { writerThread.interrupt(); writerThread.join(); table.close(); } } finally { TEST_UTIL.deleteTable(tableName); } } private void checkMinLogRolls(final HLog log, final int minRolls) throws Exception { final List<Path> paths = new ArrayList<Path>(); log.registerWALActionsListener(new WALActionsListener() { @Override public void preLogRoll(Path oldFile, Path newFile) { } @Override public void postLogRoll(Path oldFile, Path newFile) { LOG.debug("postLogRoll: oldFile=" + oldFile + " newFile=" + newFile); paths.add(newFile); } @Override public void preLogArchive(Path oldFile, Path newFile) { } @Override public void postLogArchive(Path oldFile, Path newFile) { } @Override public void logRollRequested() { } @Override public void logCloseRequested() { } @Override public void visitLogEntryBeforeWrite(HRegionInfo info, HLogKey logKey, WALEdit logEdit) { } @Override public void visitLogEntryBeforeWrite(HTableDescriptor htd, HLogKey logKey, WALEdit logEdit) { } }); // Sleep until we should get at least min-LogRoll events long wtime = System.currentTimeMillis(); Thread.sleep((minRolls + 1) * LOG_ROLL_PERIOD); // Do some extra sleep in case the machine is slow, // and the log-roll is not triggered exactly on LOG_ROLL_PERIOD. final int NUM_RETRIES = 1 + 8 * (minRolls - paths.size()); for (int retry = 0; paths.size() < minRolls && retry < NUM_RETRIES; ++retry) { Thread.sleep(LOG_ROLL_PERIOD / 4); } wtime = System.currentTimeMillis() - wtime; LOG.info(String.format("got %d rolls after %dms (%dms each) - expected at least %d rolls", paths.size(), wtime, wtime / paths.size(), minRolls)); assertFalse(paths.size() < minRolls); } }