MAPREDUCE-7095. Race conditions in closing FadvisedChunkedFile. (Miklos Szegedi via Haibo Chen)

This commit is contained in:
Haibo Chen 2018-05-10 10:42:26 -07:00
parent 1da8d4190d
commit 274eee3284
3 changed files with 98 additions and 20 deletions

View File

@ -205,8 +205,10 @@ public void run() {
// It's also possible that we'll end up requesting readahead on some
// other FD, which may be wasted work, but won't cause a problem.
try {
NativeIO.POSIX.getCacheManipulator().posixFadviseIfPossible(identifier,
fd, off, len, POSIX_FADV_WILLNEED);
if (fd.valid()) {
NativeIO.POSIX.getCacheManipulator().posixFadviseIfPossible(
identifier, fd, off, len, POSIX_FADV_WILLNEED);
}
} catch (IOException ioe) {
if (canceled) {
// no big deal - the reader canceled the request and closed

View File

@ -22,6 +22,7 @@
import java.io.IOException;
import java.io.RandomAccessFile;
import com.google.common.annotations.VisibleForTesting;
import org.apache.hadoop.io.ReadaheadPool;
import org.apache.hadoop.io.ReadaheadPool.ReadaheadRequest;
import org.apache.hadoop.io.nativeio.NativeIO;
@ -37,13 +38,14 @@ public class FadvisedChunkedFile extends ChunkedFile {
private static final Logger LOG =
LoggerFactory.getLogger(FadvisedChunkedFile.class);
private final Object closeLock = new Object();
private final boolean manageOsCache;
private final int readaheadLength;
private final ReadaheadPool readaheadPool;
private final FileDescriptor fd;
private final String identifier;
private ReadaheadRequest readaheadRequest;
private volatile ReadaheadRequest readaheadRequest;
public FadvisedChunkedFile(RandomAccessFile file, long position, long count,
int chunkSize, boolean manageOsCache, int readaheadLength,
@ -56,31 +58,50 @@ public FadvisedChunkedFile(RandomAccessFile file, long position, long count,
this.identifier = identifier;
}
@VisibleForTesting
FileDescriptor getFd() {
return fd;
}
@Override
public Object nextChunk() throws Exception {
if (manageOsCache && readaheadPool != null) {
readaheadRequest = readaheadPool
.readaheadStream(identifier, fd, getCurrentOffset(), readaheadLength,
getEndOffset(), readaheadRequest);
synchronized (closeLock) {
if (fd.valid()) {
if (manageOsCache && readaheadPool != null) {
readaheadRequest = readaheadPool
.readaheadStream(
identifier, fd, getCurrentOffset(), readaheadLength,
getEndOffset(), readaheadRequest);
}
return super.nextChunk();
} else {
return null;
}
}
return super.nextChunk();
}
@Override
public void close() throws Exception {
if (readaheadRequest != null) {
readaheadRequest.cancel();
}
if (manageOsCache && getEndOffset() - getStartOffset() > 0) {
try {
NativeIO.POSIX.getCacheManipulator().posixFadviseIfPossible(identifier,
fd,
getStartOffset(), getEndOffset() - getStartOffset(),
POSIX_FADV_DONTNEED);
} catch (Throwable t) {
LOG.warn("Failed to manage OS cache for " + identifier, t);
synchronized (closeLock) {
if (readaheadRequest != null) {
readaheadRequest.cancel();
readaheadRequest = null;
}
if (fd.valid() &&
manageOsCache && getEndOffset() - getStartOffset() > 0) {
try {
NativeIO.POSIX.getCacheManipulator().posixFadviseIfPossible(
identifier,
fd,
getStartOffset(), getEndOffset() - getStartOffset(),
POSIX_FADV_DONTNEED);
} catch (Throwable t) {
LOG.warn("Failed to manage OS cache for " + identifier +
" fd " + fd.toString(), t);
}
}
// fd becomes invalid upon closing
super.close();
}
super.close();
}
}

View File

@ -0,0 +1,55 @@
/*
* 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.mapred;
import org.junit.Test;
import java.io.File;
import java.io.RandomAccessFile;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
/**
* Unit test for FadvisedChunkedFile.
*/
public class TestFadvisedChunkedFile {
@Test
public void testDoubleClose() throws Exception {
File absoluteFile = new File("target",
TestFadvisedChunkedFile.class.getSimpleName()).getAbsoluteFile();
absoluteFile.deleteOnExit();
try {
try (RandomAccessFile f = new RandomAccessFile(
absoluteFile.getAbsolutePath(), "rw")) {
FadvisedChunkedFile af = new FadvisedChunkedFile(
f, 0, 5, 2, true,
10, null, "foo");
assertTrue("fd not valid", f.getFD().valid());
af.close();
assertFalse("fd still valid", f.getFD().valid());
af.close();
assertFalse("fd still valid", f.getFD().valid());
}
} finally {
absoluteFile.delete();
}
}
}