HDFS-7999. FsDatasetImpl#createTemporary sometimes holds the FSDatasetImpl lock for a very long time (sinago via cmccabe)

This commit is contained in:
Colin Patrick Mccabe 2015-04-06 08:54:46 -07:00
parent 53959e69f7
commit 28bebc81db
2 changed files with 52 additions and 28 deletions

View File

@ -1379,6 +1379,9 @@ Release 2.7.0 - UNRELEASED
HDFS-8051. FsVolumeList#addVolume should release volume reference if not
put it into BlockScanner. (Lei (Eddy) Xu via Colin P. McCabe)
HDFS-7999. FsDatasetImpl#createTemporary sometimes holds the FSDatasetImpl
lock for a very long time (sinago via cmccabe)
BREAKDOWN OF HDFS-7584 SUBTASKS AND RELATED JIRAS
HDFS-7720. Quota by Storage Type API, tools and ClientNameNode

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@ -1412,38 +1412,59 @@ class FsDatasetImpl implements FsDatasetSpi<FsVolumeImpl> {
}
@Override // FsDatasetSpi
public synchronized ReplicaHandler createTemporary(
public ReplicaHandler createTemporary(
StorageType storageType, ExtendedBlock b) throws IOException {
ReplicaInfo replicaInfo = volumeMap.get(b.getBlockPoolId(), b.getBlockId());
if (replicaInfo != null) {
if (replicaInfo.getGenerationStamp() < b.getGenerationStamp()
&& replicaInfo instanceof ReplicaInPipeline) {
// Stop the previous writer
((ReplicaInPipeline)replicaInfo)
.stopWriter(datanode.getDnConf().getXceiverStopTimeout());
invalidate(b.getBlockPoolId(), new Block[]{replicaInfo});
} else {
throw new ReplicaAlreadyExistsException("Block " + b +
" already exists in state " + replicaInfo.getState() +
" and thus cannot be created.");
long startTimeMs = Time.monotonicNow();
long writerStopTimeoutMs = datanode.getDnConf().getXceiverStopTimeout();
ReplicaInfo lastFoundReplicaInfo = null;
do {
synchronized (this) {
ReplicaInfo currentReplicaInfo =
volumeMap.get(b.getBlockPoolId(), b.getBlockId());
if (currentReplicaInfo == lastFoundReplicaInfo) {
if (lastFoundReplicaInfo != null) {
invalidate(b.getBlockPoolId(), new Block[] { lastFoundReplicaInfo });
}
FsVolumeReference ref =
volumes.getNextVolume(storageType, b.getNumBytes());
FsVolumeImpl v = (FsVolumeImpl) ref.getVolume();
// create a temporary file to hold block in the designated volume
File f;
try {
f = v.createTmpFile(b.getBlockPoolId(), b.getLocalBlock());
} catch (IOException e) {
IOUtils.cleanup(null, ref);
throw e;
}
ReplicaInPipeline newReplicaInfo =
new ReplicaInPipeline(b.getBlockId(), b.getGenerationStamp(), v,
f.getParentFile(), 0);
volumeMap.add(b.getBlockPoolId(), newReplicaInfo);
return new ReplicaHandler(newReplicaInfo, ref);
} else {
if (!(currentReplicaInfo.getGenerationStamp() < b
.getGenerationStamp() && currentReplicaInfo instanceof ReplicaInPipeline)) {
throw new ReplicaAlreadyExistsException("Block " + b
+ " already exists in state " + currentReplicaInfo.getState()
+ " and thus cannot be created.");
}
lastFoundReplicaInfo = currentReplicaInfo;
}
}
}
FsVolumeReference ref = volumes.getNextVolume(storageType, b.getNumBytes());
FsVolumeImpl v = (FsVolumeImpl) ref.getVolume();
// create a temporary file to hold block in the designated volume
File f;
try {
f = v.createTmpFile(b.getBlockPoolId(), b.getLocalBlock());
} catch (IOException e) {
IOUtils.cleanup(null, ref);
throw e;
}
// Hang too long, just bail out. This is not supposed to happen.
long writerStopMs = Time.monotonicNow() - startTimeMs;
if (writerStopMs > writerStopTimeoutMs) {
LOG.warn("Unable to stop existing writer for block " + b + " after "
+ writerStopMs + " miniseconds.");
throw new IOException("Unable to stop existing writer for block " + b
+ " after " + writerStopMs + " miniseconds.");
}
ReplicaInPipeline newReplicaInfo = new ReplicaInPipeline(b.getBlockId(),
b.getGenerationStamp(), v, f.getParentFile(), 0);
volumeMap.add(b.getBlockPoolId(), newReplicaInfo);
return new ReplicaHandler(newReplicaInfo, ref);
// Stop the previous writer
((ReplicaInPipeline) lastFoundReplicaInfo)
.stopWriter(writerStopTimeoutMs);
} while (true);
}
/**