[
https://issues.apache.org/jira/browse/HBASE-25287?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17250520#comment-17250520
]
Wei-Chiu Chuang commented on HBASE-25287:
-----------------------------------------
2.2 is about to EOM. Do we want to cherrypick the commit to 1.x, or are we done
here? Just saw this Jira unresolved and wanted to make sure nothing else is
left undone.
> Forgetting to unbuffer streams results in many CLOSE_WAIT sockets when
> loading files
> ------------------------------------------------------------------------------------
>
> Key: HBASE-25287
> URL: https://issues.apache.org/jira/browse/HBASE-25287
> Project: HBase
> Issue Type: Bug
> Affects Versions: 2.4.0
> Reporter: Xiaolin Ha
> Assignee: Xiaolin Ha
> Priority: Major
> Fix For: 3.0.0-alpha-1, 2.3.4, 2.5.0, 2.4.1
>
> Attachments: 1605328358304-image.png, 1605328417888-image.png,
> 1605504914256-image.png
>
>
> HBASE-9393 found seek+read will leave many CLOSE_WAIT sockets without stream
> unbuffer, which can free sockets and file descriptors held by the stream.
> In our cluster RSes with about one hundred thousand store files, we found the
> number of CLOSE_WAIT sockets increases with the number of regions opened,
> and can up to the operating system open files limit 1000000.
>
> {code:java}
> 2020-11-12 20:19:02,452 WARN [1282990092@qtp-220038608-1 - Acceptor0
> [email protected]:16030] mortbay.log: EXCEPTION
> java.io.IOException: Too many open files
> at sun.nio.ch.ServerSocketChannelImpl.accept0(Native Method)
> at
> sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:422)
> at
> sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:250)
> at
> org.mortbay.jetty.nio.SelectChannelConnector$1.acceptChannel(SelectChannelConnector.java:75)
> at
> org.mortbay.io.nio.SelectorManager$SelectSet.doSelect(SelectorManager.java:686)
> at
> org.mortbay.io.nio.SelectorManager.doSelect(SelectorManager.java:192)
> at
> org.mortbay.jetty.nio.SelectChannelConnector.accept(SelectChannelConnector.java:124)
> at
> org.mortbay.jetty.AbstractConnector$Acceptor.run(AbstractConnector.java:708)
> at
> org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
> {code}
>
> {code:java}
> [hbase@gha-data-hbase-cat0053 hbase]$ ulimit -SHn
> 1000000
> {code}
>
>
> The reason of the problem is, when store file opened,
> {code:java}
> private void open() throws IOException {
> fileInfo.initHDFSBlocksDistribution();
> long readahead = fileInfo.isNoReadahead() ? 0L : -1L;
> ReaderContext context = fileInfo.createReaderContext(false, readahead,
> ReaderType.PREAD);
> fileInfo.initHFileInfo(context);
> StoreFileReader reader = fileInfo.preStoreFileReaderOpen(context,
> cacheConf);
> if (reader == null) {
> reader = fileInfo.createReader(context, cacheConf);
> fileInfo.getHFileInfo().initMetaAndIndex(reader.getHFileReader());
> }
> ....{code}
> only createReader() unbuffered the stream. In initMetaAndIndex(), using the
> stream to read blocks, so it needs to unbuffer() the socket , too.
> We can just add try before fileInfo.initHFileInfo(context); and finally
> unbuffer() the stream at the end of the open() function.
> We fixed it on our cluster, the number of CLOSE_WAIT reduced to about 0.
>
>
--
This message was sent by Atlassian Jira
(v8.3.4#803005)
