[
https://issues.apache.org/jira/browse/FLUME-1573?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13465993#comment-13465993
]
Denny Ye commented on FLUME-1573:
---------------------------------
@Brock, you said right, UUID is standard method to distinguish unique path.
It's another choose for us.
@Arvind, collision also can be found at different bucket writers in same Sink.
There is common root cause no matter different Sinks or BucketWriters. If there
are multiple BucketWriters created at contiguous timestamp, collision would be
happen.
> Duplicated HDFS file name when multiple SinkRunner was existing
> ---------------------------------------------------------------
>
> Key: FLUME-1573
> URL: https://issues.apache.org/jira/browse/FLUME-1573
> Project: Flume
> Issue Type: Bug
> Components: Sinks+Sources
> Affects Versions: v1.2.0
> Reporter: Denny Ye
> Assignee: Denny Ye
> Fix For: v1.3.0
>
> Attachments: FLUME-1573.patch
>
>
> Multiple HDFS Sinks to write events into storage. Timeout exception is always
> happening:
> {code:xml}
> 11 Sep 2012 07:04:53,478 WARN
> [SinkRunner-PollingRunner-DefaultSinkProcessor]
> (org.apache.flume.sink.hdfs.HDFSEventSink.process:442) - HDFS IO error
> java.io.IOException: Callable timed out after 10000 ms
> at
> org.apache.flume.sink.hdfs.HDFSEventSink.callWithTimeout(HDFSEventSink.java:342)
> at
> org.apache.flume.sink.hdfs.HDFSEventSink.append(HDFSEventSink.java:713)
> at
> org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:412)
> at
> org.apache.flume.sink.DefaultSinkProcessor.process(DefaultSinkProcessor.java:68)
> at org.apache.flume.SinkRunner$PollingRunner.run(SinkRunner.java:147)
> at java.lang.Thread.run(Thread.java:619)
> Caused by: java.util.concurrent.TimeoutException
> at java.util.concurrent.FutureTask$Sync.innerGet(FutureTask.java:228)
> at java.util.concurrent.FutureTask.get(FutureTask.java:91)
> at
> org.apache.flume.sink.hdfs.HDFSEventSink.callWithTimeout(HDFSEventSink.java:335)
> ... 5 more
> {code}
> I doubted that there might be happened HDFS timeout or slowly response. As
> expected, I found the duplicated creation exception with same with at HDFS.
> Also, Flume recorded same case for duplicated file name.
> {code:xml}
> 13 Sep 2012 02:09:35,432 INFO [hdfs-hdfsSink-3-call-runner-7]
> (org.apache.flume.sink.hdfs.BucketWriter.doOpen:189) - Creating
> /FLUME/dt=2012-09-13/02-host.1347501924111.tmp
> 13 Sep 2012 02:09:36,425 INFO [hdfs-hdfsSink-4-call-runner-8]
> (org.apache.flume.sink.hdfs.BucketWriter.doOpen:189) - Creating
> /FLUME/dt=2012-09-13/02-host.1347501924111.tmp
> {code}
> Different threads were going to create same file without time conflict.
> I found the root cause might be wrong usage the AtomicLong property named
> 'fileExtensionCounter' at BucketWriter. Different threads should own same
> counter by protected with CAS, not multiple private property in each thread.
> It's useless to avoid conflict of HDFS path
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
