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.server.datanode; import static org.apache.hadoop.test.MetricsAsserts.assertCounter; import static org.apache.hadoop.test.MetricsAsserts.getMetrics; import static org.junit.Assert.assertArrayEquals; import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertNull; import static org.junit.Assert.assertTrue; import static org.junit.Assume.assumeTrue; import java.io.File; import java.util.ArrayList; 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.conf.ReconfigurationException; import org.apache.hadoop.fs.FileSystem; import org.apache.hadoop.fs.Path; import org.apache.hadoop.hdfs.DFSConfigKeys; import org.apache.hadoop.hdfs.DFSTestUtil; import org.apache.hadoop.hdfs.HdfsConfiguration; import org.apache.hadoop.hdfs.MiniDFSCluster; import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeDescriptor; import org.apache.hadoop.hdfs.server.blockmanagement.DatanodeManager; import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsDatasetSpi; import org.apache.hadoop.hdfs.server.namenode.FSNamesystem; import org.apache.hadoop.hdfs.server.protocol.VolumeFailureSummary; import org.apache.hadoop.io.IOUtils; import org.apache.log4j.Level; import org.junit.After; import org.junit.Before; import org.junit.Test; import java.io.File; import java.util.ArrayList; import org.apache.hadoop.fs.FileUtil; import static org.apache.hadoop.test.MetricsAsserts.assertCounter; import static org.apache.hadoop.test.MetricsAsserts.getMetrics; import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertTrue; import static org.junit.Assume.assumeTrue; /** * Test reporting of DN volume failure counts and metrics. */ public class TestDataNodeVolumeFailureReporting { private static final Log LOG = LogFactory.getLog(TestDataNodeVolumeFailureReporting.class); { ((Log4JLogger) TestDataNodeVolumeFailureReporting.LOG).getLogger().setLevel(Level.ALL); } private FileSystem fs; private MiniDFSCluster cluster; private Configuration conf; private String dataDir; private long volumeCapacity; // Sleep at least 3 seconds (a 1s heartbeat plus padding) to allow // for heartbeats to propagate from the datanodes to the namenode. final int WAIT_FOR_HEARTBEATS = 3000; // Wait at least (2 * re-check + 10 * heartbeat) seconds for // a datanode to be considered dead by the namenode. final int WAIT_FOR_DEATH = 15000; @Before public void setUp() throws Exception { // These tests simulate volume failures by denying execute permission on the // volume's path. On Windows, the owner of an object is always allowed // access, so we can't run these tests on Windows. assumeTrue(!Path.WINDOWS); // Allow a single volume failure (there are two volumes) initCluster(1, 2, 1); } @After public void tearDown() throws Exception { IOUtils.cleanup(LOG, fs); if (cluster != null) { for (File dir : cluster.getAllInstanceStorageDirs()) { dir.setExecutable(true); } IOUtils.cleanup(LOG, fs); cluster.shutdown(); } } /** * Test that individual volume failures do not cause DNs to fail, that * all volumes failed on a single datanode do cause it to fail, and * that the capacities and liveliness is adjusted correctly in the NN. */ @Test public void testSuccessiveVolumeFailures() throws Exception { // Bring up two more datanodes cluster.startDataNodes(conf, 2, true, null, null); cluster.waitActive(); /* * Calculate the total capacity of all the datanodes. Sleep for * three seconds to be sure the datanodes have had a chance to * heartbeat their capacities. */ Thread.sleep(WAIT_FOR_HEARTBEATS); final DatanodeManager dm = cluster.getNamesystem().getBlockManager().getDatanodeManager(); final long origCapacity = DFSTestUtil.getLiveDatanodeCapacity(dm); long dnCapacity = DFSTestUtil.getDatanodeCapacity(dm, 0); File dn1Vol1 = cluster.getInstanceStorageDir(0, 0); File dn2Vol1 = cluster.getInstanceStorageDir(1, 0); File dn3Vol1 = cluster.getInstanceStorageDir(2, 0); File dn3Vol2 = cluster.getInstanceStorageDir(2, 1); /* * Make the 1st volume directories on the first two datanodes * non-accessible. We don't make all three 1st volume directories * readonly since that would cause the entire pipeline to * fail. The client does not retry failed nodes even though * perhaps they could succeed because just a single volume failed. */ DataNodeTestUtils.injectDataDirFailure(dn1Vol1, dn2Vol1); /* * Create file1 and wait for 3 replicas (ie all DNs can still * store a block). Then assert that all DNs are up, despite the * volume failures. */ Path file1 = new Path("/test1"); DFSTestUtil.createFile(fs, file1, 1024, (short) 3, 1L); DFSTestUtil.waitReplication(fs, file1, (short) 3); ArrayList<DataNode> dns = cluster.getDataNodes(); assertTrue("DN1 should be up", dns.get(0).isDatanodeUp()); assertTrue("DN2 should be up", dns.get(1).isDatanodeUp()); assertTrue("DN3 should be up", dns.get(2).isDatanodeUp()); /* * The metrics should confirm the volume failures. */ checkFailuresAtDataNode(dns.get(0), 1, true, dn1Vol1.getAbsolutePath()); checkFailuresAtDataNode(dns.get(1), 1, true, dn2Vol1.getAbsolutePath()); checkFailuresAtDataNode(dns.get(2), 0, true); // Ensure we wait a sufficient amount of time assert (WAIT_FOR_HEARTBEATS * 10) > WAIT_FOR_DEATH; // Eventually the NN should report two volume failures DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 2, origCapacity - (1 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 2); checkFailuresAtNameNode(dm, dns.get(0), true, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), true, dn2Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(2), true); /* * Now fail a volume on the third datanode. We should be able to get * three replicas since we've already identified the other failures. */ DataNodeTestUtils.injectDataDirFailure(dn3Vol1); Path file2 = new Path("/test2"); DFSTestUtil.createFile(fs, file2, 1024, (short) 3, 1L); DFSTestUtil.waitReplication(fs, file2, (short) 3); assertTrue("DN3 should still be up", dns.get(2).isDatanodeUp()); checkFailuresAtDataNode(dns.get(2), 1, true, dn3Vol1.getAbsolutePath()); DataNodeTestUtils.triggerHeartbeat(dns.get(2)); checkFailuresAtNameNode(dm, dns.get(2), true, dn3Vol1.getAbsolutePath()); /* * Once the datanodes have a chance to heartbeat their new capacity the * total capacity should be down by three volumes (assuming the host * did not grow or shrink the data volume while the test was running). */ dnCapacity = DFSTestUtil.getDatanodeCapacity(dm, 0); DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 3, origCapacity - (3 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 3); checkFailuresAtNameNode(dm, dns.get(0), true, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), true, dn2Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(2), true, dn3Vol1.getAbsolutePath()); /* * Now fail the 2nd volume on the 3rd datanode. All its volumes * are now failed and so it should report two volume failures * and that it's no longer up. Only wait for two replicas since * we'll never get a third. */ DataNodeTestUtils.injectDataDirFailure(dn3Vol2); Path file3 = new Path("/test3"); DFSTestUtil.createFile(fs, file3, 1024, (short) 3, 1L); DFSTestUtil.waitReplication(fs, file3, (short) 2); // The DN should consider itself dead DFSTestUtil.waitForDatanodeDeath(dns.get(2)); // And report two failed volumes checkFailuresAtDataNode(dns.get(2), 2, true, dn3Vol1.getAbsolutePath(), dn3Vol2.getAbsolutePath()); // The NN considers the DN dead DFSTestUtil.waitForDatanodeStatus(dm, 2, 1, 2, origCapacity - (4 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 2); checkFailuresAtNameNode(dm, dns.get(0), true, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), true, dn2Vol1.getAbsolutePath()); /* * The datanode never tries to restore the failed volume, even if * it's subsequently repaired, but it should see this volume on * restart, so file creation should be able to succeed after * restoring the data directories and restarting the datanodes. */ DataNodeTestUtils.restoreDataDirFromFailure(dn1Vol1, dn2Vol1, dn3Vol1, dn3Vol2); cluster.restartDataNodes(); cluster.waitActive(); Path file4 = new Path("/test4"); DFSTestUtil.createFile(fs, file4, 1024, (short) 3, 1L); DFSTestUtil.waitReplication(fs, file4, (short) 3); /* * Eventually the capacity should be restored to its original value, * and that the volume failure count should be reported as zero by * both the metrics and the NN. */ DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 0, origCapacity, WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 0); dns = cluster.getDataNodes(); checkFailuresAtNameNode(dm, dns.get(0), true); checkFailuresAtNameNode(dm, dns.get(1), true); checkFailuresAtNameNode(dm, dns.get(2), true); } /** * Test that the NN re-learns of volume failures after restart. */ @Test public void testVolFailureStatsPreservedOnNNRestart() throws Exception { // Bring up two more datanodes that can tolerate 1 failure cluster.startDataNodes(conf, 2, true, null, null); cluster.waitActive(); DatanodeManager dm = cluster.getNamesystem().getBlockManager().getDatanodeManager(); long origCapacity = DFSTestUtil.getLiveDatanodeCapacity(dm); long dnCapacity = DFSTestUtil.getDatanodeCapacity(dm, 0); // Fail the first volume on both datanodes (we have to keep the // third healthy so one node in the pipeline will not fail). File dn1Vol1 = cluster.getInstanceStorageDir(0, 0); File dn2Vol1 = cluster.getInstanceStorageDir(1, 0); DataNodeTestUtils.injectDataDirFailure(dn1Vol1, dn2Vol1); Path file1 = new Path("/test1"); DFSTestUtil.createFile(fs, file1, 1024, (short) 2, 1L); DFSTestUtil.waitReplication(fs, file1, (short) 2); ArrayList<DataNode> dns = cluster.getDataNodes(); // The NN reports two volumes failures DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 2, origCapacity - (1 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 2); checkFailuresAtNameNode(dm, dns.get(0), true, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), true, dn2Vol1.getAbsolutePath()); // After restarting the NN it still see the two failures cluster.restartNameNode(0); cluster.waitActive(); dm = cluster.getNamesystem().getBlockManager().getDatanodeManager(); DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 2, origCapacity - (1 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 2); checkFailuresAtNameNode(dm, dns.get(0), true, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), true, dn2Vol1.getAbsolutePath()); } @Test public void testMultipleVolFailuresOnNode() throws Exception { // Reinitialize the cluster, configured with 4 storage locations per DataNode // and tolerating up to 2 failures. tearDown(); initCluster(3, 4, 2); // Calculate the total capacity of all the datanodes. Sleep for three seconds // to be sure the datanodes have had a chance to heartbeat their capacities. Thread.sleep(WAIT_FOR_HEARTBEATS); DatanodeManager dm = cluster.getNamesystem().getBlockManager().getDatanodeManager(); long origCapacity = DFSTestUtil.getLiveDatanodeCapacity(dm); long dnCapacity = DFSTestUtil.getDatanodeCapacity(dm, 0); File dn1Vol1 = cluster.getInstanceStorageDir(0, 0); File dn1Vol2 = cluster.getInstanceStorageDir(0, 1); File dn2Vol1 = cluster.getInstanceStorageDir(1, 0); File dn2Vol2 = cluster.getInstanceStorageDir(1, 1); // Make the first two volume directories on the first two datanodes // non-accessible. DataNodeTestUtils.injectDataDirFailure(dn1Vol1, dn1Vol2, dn2Vol1, dn2Vol2); // Create file1 and wait for 3 replicas (ie all DNs can still store a block). // Then assert that all DNs are up, despite the volume failures. Path file1 = new Path("/test1"); DFSTestUtil.createFile(fs, file1, 1024, (short) 3, 1L); DFSTestUtil.waitReplication(fs, file1, (short) 3); ArrayList<DataNode> dns = cluster.getDataNodes(); assertTrue("DN1 should be up", dns.get(0).isDatanodeUp()); assertTrue("DN2 should be up", dns.get(1).isDatanodeUp()); assertTrue("DN3 should be up", dns.get(2).isDatanodeUp()); checkFailuresAtDataNode(dns.get(0), 1, true, dn1Vol1.getAbsolutePath(), dn1Vol2.getAbsolutePath()); checkFailuresAtDataNode(dns.get(1), 1, true, dn2Vol1.getAbsolutePath(), dn2Vol2.getAbsolutePath()); checkFailuresAtDataNode(dns.get(2), 0, true); // Ensure we wait a sufficient amount of time assert (WAIT_FOR_HEARTBEATS * 10) > WAIT_FOR_DEATH; // Eventually the NN should report four volume failures DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 4, origCapacity - (1 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 4); checkFailuresAtNameNode(dm, dns.get(0), true, dn1Vol1.getAbsolutePath(), dn1Vol2.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), true, dn2Vol1.getAbsolutePath(), dn2Vol2.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(2), true); } @Test public void testDataNodeReconfigureWithVolumeFailures() throws Exception { // Bring up two more datanodes cluster.startDataNodes(conf, 2, true, null, null); cluster.waitActive(); final DatanodeManager dm = cluster.getNamesystem().getBlockManager().getDatanodeManager(); long origCapacity = DFSTestUtil.getLiveDatanodeCapacity(dm); long dnCapacity = DFSTestUtil.getDatanodeCapacity(dm, 0); // Fail the first volume on both datanodes (we have to keep the // third healthy so one node in the pipeline will not fail). File dn1Vol1 = cluster.getInstanceStorageDir(0, 0); File dn1Vol2 = cluster.getInstanceStorageDir(0, 1); File dn2Vol1 = cluster.getInstanceStorageDir(1, 0); File dn2Vol2 = cluster.getInstanceStorageDir(1, 1); DataNodeTestUtils.injectDataDirFailure(dn1Vol1); DataNodeTestUtils.injectDataDirFailure(dn2Vol1); Path file1 = new Path("/test1"); DFSTestUtil.createFile(fs, file1, 1024, (short) 2, 1L); DFSTestUtil.waitReplication(fs, file1, (short) 2); ArrayList<DataNode> dns = cluster.getDataNodes(); assertTrue("DN1 should be up", dns.get(0).isDatanodeUp()); assertTrue("DN2 should be up", dns.get(1).isDatanodeUp()); assertTrue("DN3 should be up", dns.get(2).isDatanodeUp()); checkFailuresAtDataNode(dns.get(0), 1, true, dn1Vol1.getAbsolutePath()); checkFailuresAtDataNode(dns.get(1), 1, true, dn2Vol1.getAbsolutePath()); checkFailuresAtDataNode(dns.get(2), 0, true); // Ensure we wait a sufficient amount of time assert (WAIT_FOR_HEARTBEATS * 10) > WAIT_FOR_DEATH; // The NN reports two volume failures DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 2, origCapacity - (1 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 2); checkFailuresAtNameNode(dm, dns.get(0), true, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), true, dn2Vol1.getAbsolutePath()); // Reconfigure again to try to add back the failed volumes. reconfigureDataNode(dns.get(0), dn1Vol1, dn1Vol2); reconfigureDataNode(dns.get(1), dn2Vol1, dn2Vol2); DataNodeTestUtils.triggerHeartbeat(dns.get(0)); DataNodeTestUtils.triggerHeartbeat(dns.get(1)); checkFailuresAtDataNode(dns.get(0), 1, false, dn1Vol1.getAbsolutePath()); checkFailuresAtDataNode(dns.get(1), 1, false, dn2Vol1.getAbsolutePath()); // Ensure we wait a sufficient amount of time. assert (WAIT_FOR_HEARTBEATS * 10) > WAIT_FOR_DEATH; // The NN reports two volume failures again. DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 2, origCapacity - (1 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(false, 2); checkFailuresAtNameNode(dm, dns.get(0), false, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), false, dn2Vol1.getAbsolutePath()); // Reconfigure a third time with the failed volumes. Afterwards, we expect // the same volume failures to be reported. (No double-counting.) reconfigureDataNode(dns.get(0), dn1Vol1, dn1Vol2); reconfigureDataNode(dns.get(1), dn2Vol1, dn2Vol2); DataNodeTestUtils.triggerHeartbeat(dns.get(0)); DataNodeTestUtils.triggerHeartbeat(dns.get(1)); checkFailuresAtDataNode(dns.get(0), 1, false, dn1Vol1.getAbsolutePath()); checkFailuresAtDataNode(dns.get(1), 1, false, dn2Vol1.getAbsolutePath()); // Ensure we wait a sufficient amount of time. assert (WAIT_FOR_HEARTBEATS * 10) > WAIT_FOR_DEATH; // The NN reports two volume failures again. DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 2, origCapacity - (1 * dnCapacity), WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(false, 2); checkFailuresAtNameNode(dm, dns.get(0), false, dn1Vol1.getAbsolutePath()); checkFailuresAtNameNode(dm, dns.get(1), false, dn2Vol1.getAbsolutePath()); // Replace failed volume with healthy volume and run reconfigure DataNode. // The failed volume information should be cleared. DataNodeTestUtils.restoreDataDirFromFailure(dn1Vol1, dn2Vol1); reconfigureDataNode(dns.get(0), dn1Vol1, dn1Vol2); reconfigureDataNode(dns.get(1), dn2Vol1, dn2Vol2); DataNodeTestUtils.triggerHeartbeat(dns.get(0)); DataNodeTestUtils.triggerHeartbeat(dns.get(1)); checkFailuresAtDataNode(dns.get(0), 1, true); checkFailuresAtDataNode(dns.get(1), 1, true); DFSTestUtil.waitForDatanodeStatus(dm, 3, 0, 0, origCapacity, WAIT_FOR_HEARTBEATS); checkAggregateFailuresAtNameNode(true, 0); checkFailuresAtNameNode(dm, dns.get(0), true); checkFailuresAtNameNode(dm, dns.get(1), true); } /** * Checks the NameNode for correct values of aggregate counters tracking failed * volumes across all DataNodes. * * @param expectCapacityKnown if true, then expect that the capacities of the * volumes were known before the failures, and therefore the lost capacity * can be reported * @param expectedVolumeFailuresTotal expected number of failed volumes */ private void checkAggregateFailuresAtNameNode(boolean expectCapacityKnown, int expectedVolumeFailuresTotal) { FSNamesystem ns = cluster.getNamesystem(); assertEquals(expectedVolumeFailuresTotal, ns.getVolumeFailuresTotal()); long expectedCapacityLost = getExpectedCapacityLost(expectCapacityKnown, expectedVolumeFailuresTotal); assertEquals(expectedCapacityLost, ns.getEstimatedCapacityLostTotal()); } /** * Checks a DataNode for correct reporting of failed volumes. * * @param dn DataNode to check * @param expectedVolumeFailuresCounter metric counter value for * VolumeFailures. The current implementation actually counts the number * of failed disk checker cycles, which may be different from the length of * expectedFailedVolumes if multiple disks fail in the same disk checker * cycle * @param expectCapacityKnown if true, then expect that the capacities of the * volumes were known before the failures, and therefore the lost capacity * can be reported * @param expectedFailedVolumes expected locations of failed volumes * @throws Exception if there is any failure */ private void checkFailuresAtDataNode(DataNode dn, long expectedVolumeFailuresCounter, boolean expectCapacityKnown, String... expectedFailedVolumes) throws Exception { assertCounter("VolumeFailures", expectedVolumeFailuresCounter, getMetrics(dn.getMetrics().name())); FsDatasetSpi<?> fsd = dn.getFSDataset(); assertEquals(expectedFailedVolumes.length, fsd.getNumFailedVolumes()); assertArrayEquals(expectedFailedVolumes, fsd.getFailedStorageLocations()); if (expectedFailedVolumes.length > 0) { assertTrue(fsd.getLastVolumeFailureDate() > 0); long expectedCapacityLost = getExpectedCapacityLost(expectCapacityKnown, expectedFailedVolumes.length); assertEquals(expectedCapacityLost, fsd.getEstimatedCapacityLostTotal()); } else { assertEquals(0, fsd.getLastVolumeFailureDate()); assertEquals(0, fsd.getEstimatedCapacityLostTotal()); } } /** * Checks NameNode tracking of a particular DataNode for correct reporting of * failed volumes. * * @param dm DatanodeManager to check * @param dn DataNode to check * @param expectCapacityKnown if true, then expect that the capacities of the * volumes were known before the failures, and therefore the lost capacity * can be reported * @param expectedFailedVolumes expected locations of failed volumes * @throws Exception if there is any failure */ private void checkFailuresAtNameNode(DatanodeManager dm, DataNode dn, boolean expectCapacityKnown, String... expectedFailedVolumes) throws Exception { DatanodeDescriptor dd = cluster.getNamesystem().getBlockManager().getDatanodeManager() .getDatanode(dn.getDatanodeId()); assertEquals(expectedFailedVolumes.length, dd.getVolumeFailures()); VolumeFailureSummary volumeFailureSummary = dd.getVolumeFailureSummary(); if (expectedFailedVolumes.length > 0) { assertArrayEquals(expectedFailedVolumes, volumeFailureSummary.getFailedStorageLocations()); assertTrue(volumeFailureSummary.getLastVolumeFailureDate() > 0); long expectedCapacityLost = getExpectedCapacityLost(expectCapacityKnown, expectedFailedVolumes.length); assertEquals(expectedCapacityLost, volumeFailureSummary.getEstimatedCapacityLostTotal()); } else { assertNull(volumeFailureSummary); } } /** * Returns expected capacity lost for use in assertions. The return value is * dependent on whether or not it is expected that the volume capacities were * known prior to the failures. * * @param expectCapacityKnown if true, then expect that the capacities of the * volumes were known before the failures, and therefore the lost capacity * can be reported * @param expectedVolumeFailuresTotal expected number of failed volumes * @return estimated capacity lost in bytes */ private long getExpectedCapacityLost(boolean expectCapacityKnown, int expectedVolumeFailuresTotal) { return expectCapacityKnown ? expectedVolumeFailuresTotal * volumeCapacity : 0; } /** * Initializes the cluster. * * @param numDataNodes number of datanodes * @param storagesPerDatanode number of storage locations on each datanode * @param failedVolumesTolerated number of acceptable volume failures * @throws Exception if there is any failure */ private void initCluster(int numDataNodes, int storagesPerDatanode, int failedVolumesTolerated) throws Exception { conf = new HdfsConfiguration(); conf.setLong(DFSConfigKeys.DFS_BLOCK_SIZE_KEY, 512L); /* * Lower the DN heartbeat, DF rate, and recheck interval to one second * so state about failures and datanode death propagates faster. */ conf.setInt(DFSConfigKeys.DFS_HEARTBEAT_INTERVAL_KEY, 1); conf.setInt(DFSConfigKeys.DFS_DF_INTERVAL_KEY, 1000); conf.setInt(DFSConfigKeys.DFS_NAMENODE_HEARTBEAT_RECHECK_INTERVAL_KEY, 1000); conf.setInt(DFSConfigKeys.DFS_DATANODE_FAILED_VOLUMES_TOLERATED_KEY, failedVolumesTolerated); conf.setInt(DFSConfigKeys.DFS_BLOCK_FETCHER_BUCKETS_PER_THREAD, DFSConfigKeys.DFS_NUM_BUCKETS_DEFAULT); conf.setInt(DFSConfigKeys.DFS_NUM_BUCKETS_KEY, 1); cluster = new MiniDFSCluster.Builder(conf).numDataNodes(numDataNodes) .storagesPerDatanode(storagesPerDatanode).build(); cluster.waitActive(); fs = cluster.getFileSystem(); dataDir = cluster.getDataDirectory(); long dnCapacity = DFSTestUtil .getDatanodeCapacity(cluster.getNamesystem().getBlockManager().getDatanodeManager(), 0); volumeCapacity = dnCapacity / cluster.getStoragesPerDatanode(); } /** * Reconfigure a DataNode by setting a new list of volumes. * * @param dn DataNode to reconfigure * @param newVols new volumes to configure * @throws Exception if there is any failure */ private static void reconfigureDataNode(DataNode dn, File... newVols) throws Exception { StringBuilder dnNewDataDirs = new StringBuilder(); for (File newVol : newVols) { if (dnNewDataDirs.length() > 0) { dnNewDataDirs.append(','); } dnNewDataDirs.append(newVol.getAbsolutePath()); } try { dn.reconfigurePropertyImpl(DFSConfigKeys.DFS_DATANODE_DATA_DIR_KEY, dnNewDataDirs.toString()); } catch (ReconfigurationException e) { // This can be thrown if reconfiguration tries to use a failed volume. // We need to swallow the exception, because some of our tests want to // cover this case. LOG.warn("Could not reconfigure DataNode.", e); } } }