[ http://issues.apache.org/jira/browse/DERBY-418?page=comments#action_12429473 ] Andreas Korneliussen commented on DERBY-418: --------------------------------------------
Assuming the Derby embedded JDBC driver is thread-safe, it should be safe for a result set to call its own close() method in its finalizer. If you get a dead-lock in the finalizer, it proves that it is also possible to write a multithreaded program which gets deadlocks when calling ResultSet.close, and derby then is not really MT-safe. If this happens, I think it is better to fix the embedded driver so that it really becomes MT-safe, than avoiding synchronization in the finalizer threads. As for the suggested change in 1142, I would note that If there is no synchronization in the finalizer, and you set a field in a object from it, there is no guarantee that other threads will see the modification of the field (unless, I think, it is volatile). However, I think Mayuresh has been working on this issue, so maybe he has tried that approach? Another approach could be to use a WeakHashMap to store the activations in, instead of a Vector. If all objects referring to the activation have been garbage collected, the activation will be removed from the WeakHashMap. > outofmemory error when running large query in autocommit=false mode > ------------------------------------------------------------------- > > Key: DERBY-418 > URL: http://issues.apache.org/jira/browse/DERBY-418 > Project: Derby > Issue Type: Bug > Components: Store > Affects Versions: 10.1.1.0 > Environment: I can reproduce this problem on Win2k/ T42 laptop. > jdk141. > Reporter: Sunitha Kambhampati > Assigned To: Mayuresh Nirhali > Fix For: 10.2.1.0 > > Attachments: AutoCommitTest.java > > > On the derby-user list, Chris reported tihs problem with his application and > also a repro for the problem. I am logging the jira issue so it doesnt get > lost in all the mail. > (http://www.mail-archive.com/derby-user@db.apache.org/msg01258.html) > ------from chris's post---------- > I'm running a set of ~50000 queries on one table, using inserts and updates, > and i want to be able to roll them back so i turned off autocommit using > setAutoCommit(false). As the update runs, the memory used by the JVM > increases continually until i get the following exception about 20% of the > way through: > ERROR 40XT0: An internal error was identified by RawStore module. > at > org.apache.derby.iapi.error.StandardException.newException(StandardException.java) > at org.apache.derby.impl.store.raw.xact.Xact.setActiveState(Xact.java) > at org.apache.derby.impl.store.raw.xact.Xact.openContainer(Xact.java) > at > org.apache.derby.impl.store.access.conglomerate.OpenConglomerate.init(OpenConglomerate.java) > at org.apache.derby.impl.store.access.heap.Heap.open(Heap.java) > at > org.apache.derby.impl.store.access.RAMTransaction.openConglomerate(RAMTransaction.java) > at > org.apache.derby.impl.store.access.RAMTransaction.openConglomerate(RAMTransaction.java) > at > org.apache.derby.impl.sql.catalog.DataDictionaryImpl.getDescriptorViaIndex(DataDictionaryImpl.java) > at > org.apache.derby.impl.sql.catalog.DataDictionaryImpl.locateSchemaRow(DataDictionaryImpl.java) > at > org.apache.derby.impl.sql.catalog.DataDictionaryImpl.getSchemaDescriptor(DataDictionaryImpl.java) > at > org.apache.derby.impl.sql.compile.QueryTreeNode.getSchemaDescriptor(QueryTreeNode.java) > at > org.apache.derby.impl.sql.compile.QueryTreeNode.getSchemaDescriptor(QueryTreeNode.java) > at > org.apache.derby.impl.sql.compile.FromBaseTable.bindTableDescriptor(FromBaseTable.java) > at > org.apache.derby.impl.sql.compile.FromBaseTable.bindNonVTITables(FromBaseTable.java) > at org.apache.derby.impl.sql.compile.FromList.bindTables(FromList.java) > at > org.apache.derby.impl.sql.compile.SelectNode.bindNonVTITables(SelectNode.java) > at > org.apache.derby.impl.sql.compile.DMLStatementNode.bindTables(DMLStatementNode.java) > at > org.apache.derby.impl.sql.compile.DMLStatementNode.bind(DMLStatementNode.java) > at > org.apache.derby.impl.sql.compile.ReadCursorNode.bind(ReadCursorNode.java) > at org.apache.derby.impl.sql.compile.CursorNode.bind(CursorNode.java) > at > org.apache.derby.impl.sql.GenericStatement.prepMinion(GenericStatement.java) > at > org.apache.derby.impl.sql.GenericStatement.prepare(GenericStatement.java) > at > org.apache.derby.impl.sql.conn.GenericLanguageConnectionContext.prepareInternalStatement(GenericLanguageConnectionContext.java) > at org.apache.derby.impl.jdbc.EmbedStatement.execute(EmbedStatement.java) > at > org.apache.derby.impl.jdbc.EmbedStatement.executeQuery(EmbedStatement.java) > at vi.hotspot.database.DataInterface._query(DataInterface.java:181) > at vi.hotspot.database.DataInterface.query(DataInterface.java:160) > at > vi.hotspot.database.UpdateManager.updatePartialTable(UpdateManager.java:518) > at > vi.hotspot.database.UpdateManager.updatePartialTables(UpdateManager.java:619) > at vi.hotspot.database.UpdateManager.run(UpdateManager.java:924) > at java.lang.Thread.run(Thread.java:534) > vi.hotspot.exception.ServerTransactionException > at > vi.hotspot.database.UpdateManager.updatePartialTable(UpdateManager.java:555) > at > vi.hotspot.database.UpdateManager.updatePartialTables(UpdateManager.java:619) > at vi.hotspot.database.UpdateManager.run(UpdateManager.java:924) > at java.lang.Thread.run(Thread.java:534) > Derby is running in standalone mode. -- 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
