[
https://issues.apache.org/jira/browse/ISIS-1134?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Martin Grigorov updated ISIS-1134:
----------------------------------
Description:
My application failed twice with OutOfMemoryError in heap space so I've dumped
a .hprof of its memory (jmap -dump:format=b,file=some-file.hprof) and analyzed
it with Eclipse MAT (https://eclipse.org/mat/).
It appears that there are many org.datanucleus.store.rdbms.query.JDOQLQuery$2
objects.
JDOQLQuery$2 appears to be ManagedConnectionResourceListener (
https://github.com/datanucleus/datanucleus-rdbms/blob/651c77ff3b2af76ada97d14b537cd41fb0524a0c/src/java/org/datanucleus/store/rdbms/query/JDOQLQuery.java#L740).
The listener is removed only when
org.datanucleus.store.query.AbstractQueryResult#close() method is called.
org.apache.isis.objectstore.jdo.datanucleus.persistence.queries.PersistenceQueryFindAllInstancesProcessor#process()
does:
{code}
final List<?> pojos = (List<?>) jdoQuery.execute();
return loadAdapters(specification, pojos);
{code}
So it consumes the result and returns ObjectAdapter for each pojo but it
doesn't close the Query.
AFAIK open-session-in-view pattern is not used in Isis so the resources should
be closed explicitly after usage.
A simple solution is to try/finally this code and close the query but I may
miss some detail here.
Related: recently I've profiled the application with Yourkit and it showed that
DomainObjectContainer#allMatches() method is slow in one of the use cases. Some
quick investigation showed that DomainObjectContainer delegates the work to
org.apache.isis.objectstore.jdo.datanucleus.persistence.queries.PersistenceQueryProcessor#process().
It loads the POJOs from the DB, then wraps them in ObjectAdapters, and finally
org.apache.isis.core.metamodel.services.container.DomainObjectContainerDefault#allMatches(org.apache.isis.applib.query.Query<T>)
unwraps them back to POJOs.
Why this is done?
This solves the issue of "consume the QueryResult before closing it" for the
memory leak issue but it also adds to the processing time.
was:
My application failed twice with OutOfMemoryError in heap space so I've dumped
a .hprof of its memory (jmap -dump:format=b,file=some-file.hprof) and analyzed
it with Eclipse MAT (https://eclipse.org/mat/).
It appears that there are many org.datanucleus.store.rdbms.query.JDOQLQuery$2
objects.
JDOQLQuery$2 appears to be ManagedConnectionResourceListener (
https://github.com/datanucleus/datanucleus-rdbms/blob/651c77ff3b2af76ada97d14b537cd41fb0524a0c/src/java/org/datanucleus/store/rdbms/query/JDOQLQuery.java#L740).
The listener is removed only when
org.datanucleus.store.query.AbstractQueryResult#close() method is called.
org.apache.isis.objectstore.jdo.datanucleus.persistence.queries.PersistenceQueryFindAllInstancesProcessor#process()
does:
{code}
final List<?> pojos = (List<?>) jdoQuery.execute();
return loadAdapters(specification, pojos);
{code}
So it consumes the result and returns ObjectAdapter for each pojo but it
doesn't close the Query.
AFAIK open-session-in-view pattern is not used in Isis so the resources should
be closed explicitly after usage.
A simple solution is to try/finally this code and close the query but I may
miss some detail here.
Related: recently I've profiled the application with Yourkit and it showed that
DomainObjectContainer#allMatches() method is slow in a use case. Some quick
investigation showed that DomainObjectContainer delegates the work to
org.apache.isis.objectstore.jdo.datanucleus.persistence.queries.PersistenceQueryProcessor#process().
It loads the POJOs from the DB, then wraps them in ObjectAdapter, and finally
org.apache.isis.core.metamodel.services.container.DomainObjectContainerDefault#allMatches(org.apache.isis.applib.query.Query<T>)
unwraps them back to POJOs.
Why this is done?
This solves the issue of "consume the QueryResult before closing it" for the
memory leak issue but it also adds to the processing time.
> DN connections leak due to non-closed queries (?!)
> --------------------------------------------------
>
> Key: ISIS-1134
> URL: https://issues.apache.org/jira/browse/ISIS-1134
> Project: Isis
> Issue Type: Bug
> Components: Core
> Affects Versions: core-1.8.0
> Reporter: Martin Grigorov
> Assignee: Dan Haywood
>
> My application failed twice with OutOfMemoryError in heap space so I've
> dumped a .hprof of its memory (jmap -dump:format=b,file=some-file.hprof) and
> analyzed it with Eclipse MAT (https://eclipse.org/mat/).
> It appears that there are many org.datanucleus.store.rdbms.query.JDOQLQuery$2
> objects.
> JDOQLQuery$2 appears to be ManagedConnectionResourceListener (
> https://github.com/datanucleus/datanucleus-rdbms/blob/651c77ff3b2af76ada97d14b537cd41fb0524a0c/src/java/org/datanucleus/store/rdbms/query/JDOQLQuery.java#L740).
> The listener is removed only when
> org.datanucleus.store.query.AbstractQueryResult#close() method is called.
> org.apache.isis.objectstore.jdo.datanucleus.persistence.queries.PersistenceQueryFindAllInstancesProcessor#process()
> does:
> {code}
> final List<?> pojos = (List<?>) jdoQuery.execute();
> return loadAdapters(specification, pojos);
> {code}
> So it consumes the result and returns ObjectAdapter for each pojo but it
> doesn't close the Query.
> AFAIK open-session-in-view pattern is not used in Isis so the resources
> should be closed explicitly after usage.
> A simple solution is to try/finally this code and close the query but I may
> miss some detail here.
> Related: recently I've profiled the application with Yourkit and it showed
> that DomainObjectContainer#allMatches() method is slow in one of the use
> cases. Some quick investigation showed that DomainObjectContainer delegates
> the work to
> org.apache.isis.objectstore.jdo.datanucleus.persistence.queries.PersistenceQueryProcessor#process().
> It loads the POJOs from the DB, then wraps them in ObjectAdapters, and
> finally
> org.apache.isis.core.metamodel.services.container.DomainObjectContainerDefault#allMatches(org.apache.isis.applib.query.Query<T>)
> unwraps them back to POJOs.
> Why this is done?
> This solves the issue of "consume the QueryResult before closing it" for the
> memory leak issue but it also adds to the processing time.
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