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https://issues.apache.org/jira/browse/HDFS-17916?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=18080753#comment-18080753
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ASF GitHub Bot commented on HDFS-17916:
---------------------------------------
charlesconnell commented on code in PR #8466:
URL: https://github.com/apache/hadoop/pull/8466#discussion_r3236835008
##########
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/util/TestPipelineCloseRecoveryByteArrayLeak.java:
##########
@@ -0,0 +1,103 @@
+/**
+ * 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.util;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.DFSClientFaultInjector;
+import org.apache.hadoop.hdfs.DFSTestUtil;
+import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.HdfsConfiguration;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
+import org.apache.hadoop.hdfs.util.ByteArrayManager.ManagerMap;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Timeout;
+import org.mockito.Mockito;
+
+/**
+ * Regression test for HDFS-17916: when the streamer hits an error in the
+ * PIPELINE_CLOSE stage and recovers via processDatanodeOrExternalError(),
+ * the end-of-block DFSPacket's buffer must be returned to the
+ * {@link ByteArrayManager}; otherwise it is leaked.
+ */
+public class TestPipelineCloseRecoveryByteArrayLeak {
+
+ @Test
+ @Timeout(120)
+ public void itReleasesEndOfBlockBufferAfterPipelineCloseRecovery()
+ throws Exception {
+ DFSClientFaultInjector fault = Mockito.mock(DFSClientFaultInjector.class);
+ DFSClientFaultInjector original = DFSClientFaultInjector.get();
+ DFSClientFaultInjector.set(fault);
+
+ Configuration conf = new HdfsConfiguration();
+ conf.setBoolean(
+ HdfsClientConfigKeys.Write.ByteArrayManager.ENABLED_KEY, true);
+ // Threshold 0 means the FixedLengthManager is created on the very first
+ // allocation of a given length. The end-of-block DFSPacket uses its own
+ // (smaller) buffer length, distinct from data packets, so we need every
+ // allocation to be tracked from the start.
+ conf.setInt(
+ HdfsClientConfigKeys.Write.ByteArrayManager.COUNT_THRESHOLD_KEY, 0);
+ conf.setInt(
+ HdfsClientConfigKeys.BlockWrite.LOCATEFOLLOWINGBLOCK_RETRIES_KEY, 3);
+
+ // Force every last-in-block ack to be reported as failed; this is what
+ // drives the streamer through processDatanodeOrExternalError() with
+ // stage == PIPELINE_CLOSE.
+ Mockito.when(fault.failPacket()).thenReturn(true);
+
+ MiniDFSCluster cluster = null;
+ try {
Review Comment:
done
##########
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/util/TestPipelineCloseRecoveryByteArrayLeak.java:
##########
@@ -0,0 +1,103 @@
+/**
+ * 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.util;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.DFSClientFaultInjector;
+import org.apache.hadoop.hdfs.DFSTestUtil;
+import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.HdfsConfiguration;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
+import org.apache.hadoop.hdfs.util.ByteArrayManager.ManagerMap;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Timeout;
+import org.mockito.Mockito;
+
+/**
+ * Regression test for HDFS-17916: when the streamer hits an error in the
+ * PIPELINE_CLOSE stage and recovers via processDatanodeOrExternalError(),
+ * the end-of-block DFSPacket's buffer must be returned to the
+ * {@link ByteArrayManager}; otherwise it is leaked.
+ */
+public class TestPipelineCloseRecoveryByteArrayLeak {
+
+ @Test
+ @Timeout(120)
+ public void itReleasesEndOfBlockBufferAfterPipelineCloseRecovery()
+ throws Exception {
+ DFSClientFaultInjector fault = Mockito.mock(DFSClientFaultInjector.class);
+ DFSClientFaultInjector original = DFSClientFaultInjector.get();
+ DFSClientFaultInjector.set(fault);
+
+ Configuration conf = new HdfsConfiguration();
+ conf.setBoolean(
+ HdfsClientConfigKeys.Write.ByteArrayManager.ENABLED_KEY, true);
+ // Threshold 0 means the FixedLengthManager is created on the very first
+ // allocation of a given length. The end-of-block DFSPacket uses its own
+ // (smaller) buffer length, distinct from data packets, so we need every
+ // allocation to be tracked from the start.
+ conf.setInt(
+ HdfsClientConfigKeys.Write.ByteArrayManager.COUNT_THRESHOLD_KEY, 0);
+ conf.setInt(
+ HdfsClientConfigKeys.BlockWrite.LOCATEFOLLOWINGBLOCK_RETRIES_KEY, 3);
+
+ // Force every last-in-block ack to be reported as failed; this is what
+ // drives the streamer through processDatanodeOrExternalError() with
+ // stage == PIPELINE_CLOSE.
+ Mockito.when(fault.failPacket()).thenReturn(true);
+
+ MiniDFSCluster cluster = null;
+ try {
+ cluster = new MiniDFSCluster.Builder(conf).numDataNodes(3).build();
+ cluster.waitActive();
+ DistributedFileSystem fs = cluster.getFileSystem();
+
+ Path file = new Path("/pipelineCloseRecoveryLeak.dat");
+ DFSTestUtil.createFile(fs, file, 1024 * 1024L, (short) 3, 0L);
+
+ ByteArrayManager bam =
+ fs.getClient().getClientContext().getByteArrayManager();
+ assertTrue(bam instanceof ByteArrayManager.Impl,
Review Comment:
done
##########
hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/util/TestPipelineCloseRecoveryByteArrayLeak.java:
##########
@@ -0,0 +1,103 @@
+/**
+ * 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.util;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.hdfs.DFSClientFaultInjector;
+import org.apache.hadoop.hdfs.DFSTestUtil;
+import org.apache.hadoop.hdfs.DistributedFileSystem;
+import org.apache.hadoop.hdfs.HdfsConfiguration;
+import org.apache.hadoop.hdfs.MiniDFSCluster;
+import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
+import org.apache.hadoop.hdfs.util.ByteArrayManager.ManagerMap;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.Timeout;
+import org.mockito.Mockito;
+
+/**
+ * Regression test for HDFS-17916: when the streamer hits an error in the
+ * PIPELINE_CLOSE stage and recovers via processDatanodeOrExternalError(),
+ * the end-of-block DFSPacket's buffer must be returned to the
+ * {@link ByteArrayManager}; otherwise it is leaked.
+ */
+public class TestPipelineCloseRecoveryByteArrayLeak {
+
+ @Test
+ @Timeout(120)
+ public void itReleasesEndOfBlockBufferAfterPipelineCloseRecovery()
+ throws Exception {
+ DFSClientFaultInjector fault = Mockito.mock(DFSClientFaultInjector.class);
+ DFSClientFaultInjector original = DFSClientFaultInjector.get();
+ DFSClientFaultInjector.set(fault);
+
+ Configuration conf = new HdfsConfiguration();
+ conf.setBoolean(
+ HdfsClientConfigKeys.Write.ByteArrayManager.ENABLED_KEY, true);
+ // Threshold 0 means the FixedLengthManager is created on the very first
+ // allocation of a given length. The end-of-block DFSPacket uses its own
+ // (smaller) buffer length, distinct from data packets, so we need every
+ // allocation to be tracked from the start.
+ conf.setInt(
+ HdfsClientConfigKeys.Write.ByteArrayManager.COUNT_THRESHOLD_KEY, 0);
+ conf.setInt(
+ HdfsClientConfigKeys.BlockWrite.LOCATEFOLLOWINGBLOCK_RETRIES_KEY, 3);
+
+ // Force every last-in-block ack to be reported as failed; this is what
+ // drives the streamer through processDatanodeOrExternalError() with
+ // stage == PIPELINE_CLOSE.
+ Mockito.when(fault.failPacket()).thenReturn(true);
+
+ MiniDFSCluster cluster = null;
+ try {
+ cluster = new MiniDFSCluster.Builder(conf).numDataNodes(3).build();
+ cluster.waitActive();
+ DistributedFileSystem fs = cluster.getFileSystem();
+
+ Path file = new Path("/pipelineCloseRecoveryLeak.dat");
+ DFSTestUtil.createFile(fs, file, 1024 * 1024L, (short) 3, 0L);
+
+ ByteArrayManager bam =
+ fs.getClient().getClientContext().getByteArrayManager();
+ assertTrue(bam instanceof ByteArrayManager.Impl,
+ "expected bounded ByteArrayManager but got "
+ + bam.getClass().getName());
+
+ ManagerMap managers = ((ByteArrayManager.Impl) bam).getManagers();
+ // After the writer closes, every DFSPacket that the streamer pulled
+ // off the dataQueue must have had its buffer recycled. Without the
+ // HDFS-17916 fix, the end-of-block packet from the PIPELINE_CLOSE
+ // recovery path leaks one buffer, so countAllocated() stays > 0.
+ // release() is performed by the streamer thread, so allow a brief
+ // moment for that thread to settle after close() returns.
+ GenericTestUtils.waitFor(() -> managers.countAllocated() == 0, 50, 5000);
+ assertEquals(0, managers.countAllocated(),
Review Comment:
done
> DataStreamer#processDatanodeOrExternalError() fails to return byte arrays to
> ByteArrayManager
> ---------------------------------------------------------------------------------------------
>
> Key: HDFS-17916
> URL: https://issues.apache.org/jira/browse/HDFS-17916
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: hdfs-client
> Affects Versions: 3.3.6, 3.5.0, 3.4.3
> Reporter: Charles Connell
> Priority: Major
> Labels: pull-request-available
>
> A [certain code
> path|https://github.com/apache/hadoop/blob/b322c3ce2c10b45cec2f9acbe6f00fb75c054caa/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DataStreamer.java#L1422]
> in the DFS client DataStreamer discards DFSPacket objects without returning
> their contained byte arrays to the ByteArrayManager. I discovered this bug at
> my company after we had HBase server threads hung for hours at
> {{{}ByteArrayManager#allocate(){}}}. Because the leak only happens in an
> error-handling path, the problem requires an unhealthy HDFS cluster in order
> to be exposed.
> I took a heap dump of a high-uptime but relatively healthy HBase server, and
> found evidence of leaked byte arrays there too. In the heap dump, the two
> FixedLengthManagers both had {{{}numAllocated = 9{}}}, but there were zero
> live {{DFSPacket}} objects. This suggests that the byte arrays, and their
> containing {{DFSPackets}} had been garbage collected, unbeknownst to
> {{{}FixedLengthManager{}}}.
> In DataStreamer.java starting at line 1410, the {{DFSPacket}} that is
> {{{}remove(){}}}'d from {{dataQueue}} is allowed to be garbage collected
> without further interaction.
> {code:java}
> if (!streamerClosed && dfsClient.clientRunning) {
> if (stage == BlockConstructionStage.PIPELINE_CLOSE) { // If we
> had an error while closing the pipeline, we go through a fast-path
> // where the BlockReceiver does not run. Instead, the DataNode just
> finalizes
> // the block immediately during the 'connect ack' process. So, we
> want to pull
> // the end-of-block packet from the dataQueue, since we don't
> actually have
> // a true pipeline to send it over.
> //
> // We also need to set lastAckedSeqno to the end-of-block Packet's
> seqno, so that
> // a client waiting on close() will be aware that the flush finished.
> synchronized (dataQueue) {
> DFSPacket endOfBlockPacket = dataQueue.remove(); // remove the end
> of block packet
> // Close any trace span associated with this Packet
> Span span = endOfBlockPacket.getSpan();
> if (span != null) {
> span.finish();
> endOfBlockPacket.setSpan(null);
> }
> assert endOfBlockPacket.isLastPacketInBlock();
> assert lastAckedSeqno == endOfBlockPacket.getSeqno() - 1;
> lastAckedSeqno = endOfBlockPacket.getSeqno();
> pipelineRecoveryCount = 0;
> dataQueue.notifyAll();
> }
> endBlock();
> } else {
> initDataStreaming();
> }
> } {code}
> This could be fixed by inserting this line somewhere above:
> {code:java}
> endOfBlockPacket.releaseBuffer(byteArrayManager);
> {code}
> Claude Opus 4.7 was used to assist in finding this bug. I verified the
> findings and I stand by them.
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