[ https://issues.apache.org/jira/browse/HIVE-14187?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Mohit Sabharwal updated HIVE-14187: ----------------------------------- Description: JDOPersistenceManager objects are cached in JDOPersistenceManagerFactory by DataNuclues. A new JDOPersistenceManager object gets created for every HMS thread since ObjectStore is a thread local. In non-embedded metastore mode, JDOPersistenceManager associated with a thread only gets cleaned up if IMetaStoreClient#close is called by the client (which calls ObjectStore#shutdown which calls JDOPersistenceManager#close which in turn removes the object from cache in JDOPersistenceManagerFactory#releasePersistenceManager https://github.com/datanucleus/datanucleus-api-jdo/blob/master/src/main/java/org/datanucleus/api/jdo/JDOPersistenceManagerFactory.java#L1271), i.e. the object will remain cached if client does not call close. For example: If one interrupts out of hive CLI shell (instead of using 'exit;' command), SessionState#close does not get called, and hence IMetaStoreClient#close does not get called. Instead of relying the client to call close, it's cleaner to automatically perform RawStore related cleanup at the server end via deleteContext() which gets called when the server detects a lost/closed connection. was: JDOPersistenceManager objects are cached in JDOPersistenceManagerFactory by DataNuclues. A new JDOPersistenceManager object gets created for every HMS thread local since ObjectStore is a thread local. In non-embedded metastore mode, JDOPersistenceManager associated with a thread only gets cleaned up if IMetaStoreClient#close is called by the client (which calls ObjectStore#shutdown which calls JDOPersistenceManager#close which in turn removes the object from cache in JDOPersistenceManagerFactory#releasePersistenceManager https://github.com/datanucleus/datanucleus-api-jdo/blob/master/src/main/java/org/datanucleus/api/jdo/JDOPersistenceManagerFactory.java#L1271), i.e. the object will remain cached if client does not call close. For example: If one interrupts out of hive CLI shell (instead of using 'exit;' command), SessionState#close does not get called, and hence IMetaStoreClient#close does not get called. Instead of relying the client to call close, it's cleaner to automatically perform RawStore related cleanup at the server end via deleteContext() which gets called when the server detects a lost/closed connection. > JDOPersistenceManager objects remain cached if MetaStoreClient#close is not > called > ---------------------------------------------------------------------------------- > > Key: HIVE-14187 > URL: https://issues.apache.org/jira/browse/HIVE-14187 > Project: Hive > Issue Type: Bug > Reporter: Mohit Sabharwal > Assignee: Mohit Sabharwal > Attachments: HIVE-14187.patch > > > JDOPersistenceManager objects are cached in JDOPersistenceManagerFactory by > DataNuclues. > A new JDOPersistenceManager object gets created for every HMS thread since > ObjectStore is a thread local. > In non-embedded metastore mode, JDOPersistenceManager associated with a > thread only gets cleaned up if IMetaStoreClient#close is called by the client > (which calls ObjectStore#shutdown which calls JDOPersistenceManager#close > which in turn removes the object from cache in > JDOPersistenceManagerFactory#releasePersistenceManager > https://github.com/datanucleus/datanucleus-api-jdo/blob/master/src/main/java/org/datanucleus/api/jdo/JDOPersistenceManagerFactory.java#L1271), > i.e. the object will remain cached if client does not call close. > For example: If one interrupts out of hive CLI shell (instead of using > 'exit;' command), SessionState#close does not get called, and hence > IMetaStoreClient#close does not get called. > Instead of relying the client to call close, it's cleaner to automatically > perform RawStore related cleanup at the server end via deleteContext() which > gets called when the server detects a lost/closed connection. -- This message was sent by Atlassian JIRA (v6.3.4#6332)