[ http://issues.apache.org/jira/browse/DERBY-210?page=comments#action_12363684 ]
Daniel John Debrunner commented on DERBY-210: --------------------------------------------- Couple of issues here: 1) Doing anything complex in a finalizer can be trouble, as the order of finalizer execution is not guaranteed and so any synchronization can lead to deadlocks. The embedded engine works around this by having the finalizer just mark some object as not being used any more and some later action on the connection will also cleanup the finailzed object. 2) I think the actions of Statement.close() need to be investigated, I didn't think that Statement.close() had anyrelationship to automcommit and issuing a COMMIT. Section 10.1 of JDBC 3.0 has no mention of Statement.close(). > Network Server will leak prepared statements if not explicitly closed by the > user until the connection is closed > ---------------------------------------------------------------------------------------------------------------- > > Key: DERBY-210 > URL: http://issues.apache.org/jira/browse/DERBY-210 > Project: Derby > Type: Bug > Components: Network Client > Reporter: Kathey Marsden > Assignee: Deepa Remesh > Attachments: derby-210.diff, derby-210.status, derbyStress.java > > Network server will not garbage collect prepared statements that are not > explicitly closed by the user. So a loop like this will leak. > ... > PreparedStatement ps; > for (int i = 0 ; i < numPs; i++) > { > ps = conn.prepareStatement(selTabSql); > rs =ps.executeQuery(); > while (rs.next()) > { > rs.getString(1); > } > rs.close(); > // I'm a sloppy java programmer > //ps.close(); > } > > To reproduce run the attached program > java derbyStress > Both client and server will grow until the connection is closed. > > It is likely that the fix for this will have to be in the client. The client > does not send protocol to close the prepared statement, but rather reuses the > PKGNAMCSN on the PRPSQLSTT request once the prepared statement has been > closed. This is how the server knows to close the old statement and create a > new one. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
