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https://issues.apache.org/jira/browse/HBASE-13238?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14361448#comment-14361448
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Andrew Purtell commented on HBASE-13238:
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bq. SocketIOWithTimeout does not timeout? So why does it have a 'Timeout' in
its name...
Beats me.
FWIW, I dumped the stack of the regionserver several times over a period of
hours and the thread in question had the same stack trace each time.
Even if we get hung up at the HDFS level, it's our problem, we can't just have
indefinite unavailability in some known circumstances.
> Time out locks and abort if HDFS is wedged
> ------------------------------------------
>
> Key: HBASE-13238
> URL: https://issues.apache.org/jira/browse/HBASE-13238
> Project: HBase
> Issue Type: Brainstorming
> Reporter: Andrew Purtell
>
> This is a brainstorming issue on the topic of timing out locks and aborting
> rather than waiting infinitely. Perhaps even as a rule.
> We had a minor production incident where a region was unable to close after
> trying for 24 hours. The CloseRegionHandler was waiting for a write lock on
> the ReentrantReadWriteLock we take in HRegion#doClose. There were outstanding
> read locks. Three other threads were stuck in scanning, all blocked on the
> same DFSInputStream. Two were blocked in DFSInputStream#getFileLength, the
> third was waiting in epoll from SocketIOWithTimeout$SelectorPool#select with
> apparent infinite timeout from PacketReceiver#readChannelFully.
> This is similar to other issues we have seen before, in the context of the
> region wanting to finish a compaction before closing for a split, but can't
> due to some HDFS issue causing the reader to become extremely slow if not
> wedged. This has lead to what should be quick SplitTransactions causing
> availability problems of many minutes in length.
> The Hadoop version was 2.3 (specifically 2.3 CDH 5.0.1), and we are planning
> to upgrade, but [~lhofhansl] and I were discussing the issue in general and
> wonder if we should not be timing out locks such as the
> ReentrantReadWriteLock, and if so, abort the regionserver. In this case this
> would have caused recovery and reassignment of the region in question and we
> would not have had a prolonged availability problem.
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