[ 
http://issues.apache.org/jira/browse/DERBY-418?page=comments#action_12427480 ] 
            
Mayuresh Nirhali commented on DERBY-418:
----------------------------------------

I used the JHAT (jdk1.6) to dump the java heap and observed that large number 
of generated objects of type CursorActivation exist on the heap. The expected 
behavior here is to have not more than 1 Activation when the statement is being 
executed. Further investigation showed that these generated objects are not 
getting closed for only the "select" kind statements. 
The GenericPreparedStatement fires activation.execute method and gets the 
result in a ResultSet object. It then checks if the singleExecution flag for 
activation is true and the returned resultSet is closed. If both are true then 
the activation is closed. For the "select" statements in the reproducible 
testcase, the returned resultSet is not closed and hence the activation is NOT 
closed. Thus causing the memory leak.

The code for activation.execute is dynamically generated code. I need some help 
to understand how this can be debugged.
Before that, I would like to understand if the returned resultSet should really 
be closed for "select" statement ?? If Yes, then when the activation is 
expected to be closed for such case ?? 

> 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
>             Fix For: 10.2.0.0
>
>         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/[email protected]/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. 

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