[
https://issues.apache.org/jira/browse/HBASE-16032?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15333000#comment-15333000
]
Yu Li commented on HBASE-16032:
-------------------------------
Unfortunately, the logging level of RpcServer in the problematic machine was
INFO rather than DEBUG, so we missed the logging of exception details in
{{CallRunner#run}}, and the client customer didn't report any exception either.
But during the RS fullGC period there was some HDFS problem, so I guess (yep
sorry only my guess...) the cause was HDFS related exceptions.
> Possible memory leak in StoreScanner
> ------------------------------------
>
> Key: HBASE-16032
> URL: https://issues.apache.org/jira/browse/HBASE-16032
> Project: HBase
> Issue Type: Bug
> Affects Versions: 1.2.1, 1.1.5, 0.98.20
> Reporter: Yu Li
> Assignee: Yu Li
> Fix For: 2.0.0, 1.3.0, 1.2.2, 1.1.6, 0.98.21
>
> Attachments: HBASE-16032.patch
>
>
> We observed frequent fullGC of RS in our production environment, and after
> analyzing the heapdump, we found large memory occupancy by
> HStore#changedReaderObservers, the map is surprisingly containing 7500w
> objects...
> After some debugging, I located some possible memory leak in StoreScanner
> constructor:
> {code}
> public StoreScanner(Store store, ScanInfo scanInfo, Scan scan, final
> NavigableSet<byte[]> columns,
> long readPt)
> throws IOException {
> this(store, scan, scanInfo, columns, readPt, scan.getCacheBlocks());
> if (columns != null && scan.isRaw()) {
> throw new DoNotRetryIOException("Cannot specify any column for a raw
> scan");
> }
> matcher = new ScanQueryMatcher(scan, scanInfo, columns,
> ScanType.USER_SCAN, Long.MAX_VALUE, HConstants.LATEST_TIMESTAMP,
> oldestUnexpiredTS, now, store.getCoprocessorHost());
> this.store.addChangedReaderObserver(this);
> // Pass columns to try to filter out unnecessary StoreFiles.
> List<KeyValueScanner> scanners = getScannersNoCompaction();
> ...
> seekScanners(scanners, matcher.getStartKey(), explicitColumnQuery
> && lazySeekEnabledGlobally, parallelSeekEnabled);
> ...
> resetKVHeap(scanners, store.getComparator());
> }
> {code}
> If there's any Exception thrown after
> {{this.store.addChangedReaderObserver(this)}}, the returned scanner might be
> null and there's no chance to remove the scanner from changedReaderObservers,
> like in HRegion#get
> {code}
> RegionScanner scanner = null;
> try {
> scanner = getScanner(scan);
> scanner.next(results);
> } finally {
> if (scanner != null)
> scanner.close();
> }
> {code}
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
