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Lefty Leverenz commented on HIVE-13754: --------------------------------------- [~cdrome], please specify Target Version instead of Fix Version – use the Edit button (top left). Thanks. > Fix resource leak in HiveClientCache > ------------------------------------ > > Key: HIVE-13754 > URL: https://issues.apache.org/jira/browse/HIVE-13754 > Project: Hive > Issue Type: Bug > Components: Clients > Affects Versions: 1.2.1, 2.0.0 > Reporter: Chris Drome > Assignee: Chris Drome > Fix For: 1.2.1, 2.0.0 > > Attachments: HIVE-13754-branch-1.patch, HIVE-13754.patch > > > Found that the {{users}} reference count can go into negative values, which > prevents {{tearDownIfUnused}} from closing the client connection when called. > This leads to a build up of clients which have been evicted from the cache, > are no longer in use, but have not been shutdown. > GC will eventually call {{finalize}}, which forcibly closes the connection > and cleans up the client, but I have seen as many as several hundred open > client connections as a result. > The main resource for this is caused by RetryingMetaStoreClient, which will > call {{reconnect}} on acquire, which calls {{close}}. This will decrement > {{users}} to -1 on the reconnect, then acquire will increase this to 0 while > using it, and back to -1 when it releases it. -- This message was sent by Atlassian JIRA (v6.3.4#6332)