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Varun Sharma commented on HBASE-8285: ------------------------------------- I attached v4 for 0.94 with Nicholas' comment incorporated into it. [~te...@apache.org] - I still need make similar changes for trunk and attach a patch. Will do that today... Thanks Varun > HBaseClient never recovers for single HTable.get() calls with no retries when > regions move > ------------------------------------------------------------------------------------------ > > Key: HBASE-8285 > URL: https://issues.apache.org/jira/browse/HBASE-8285 > Project: HBase > Issue Type: Bug > Components: Client > Affects Versions: 0.94.6.1 > Reporter: Varun Sharma > Assignee: Varun Sharma > Priority: Critical > Fix For: 0.98.0, 0.94.7, 0.95.1 > > Attachments: 8285-0.94.txt, 8285-0.94-v2.txt, 8285-0.94-v3.txt, > 8285-0.94-v4.txt, 8285-trunk.txt, 8285-trunk-v2.txt > > > Steps to reproduce this bug: > 1) Gracefull restart a region server causing regions to get redistributed. > 2) Client call to this region keeps failing since Meta Cache is never purged > on the client for the region that moved. > Reason behind the bug: > 1) Client continues to hit the old region server. > 2) The old region server throws NotServingRegionException which is not > handled correctly and the META cache entries are never purged for that server > causing the client to keep hitting the old server. > The reason lies in ServerCallable code since we only purge META cache entries > when there is a RetriesExhaustedException, SocketTimeoutException or > ConnectException. However, there is no case check for > NotServingRegionException(s). > Why is this not a problem for Scan(s) and Put(s) ? > a) If a region server is not hosting a region/scanner, then an > UnknownScannerException is thrown which causes a relocateRegion() call > causing a refresh of the META cache for that particular region. > b) For put(s), the processBatchCallback() interface in HConnectionManager is > used which clears out META cache entries for all kinds of exceptions except > DoNotRetryException. -- 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