Grouper Developers Forum

[Chris Hyzer <>]

I went ahead and made these fixed in 1.4 (synchronize the delete, and delete 
the cache when GrouperSession stop()).  Can you do three things?  :

################################
1. Get the latest Grouper 1.4 branch API (if you aren't on 1.4.2, see the 
change log for upgrade instructions):

cvs 
-d:pserver::/home/cvs/i2mi
 login 

cvs 
-d:pserver::/home/cvs/i2mi
 export -r GROUPER_1_4_BRANCH grouper

cd grouper

export ANT_HOME=/home/appadmin/software/apache-ant-1.7.0

/home/appadmin/software/apache-ant-1.7.0/bin/ant dist

###############################

2. Make sure to stop any GrouperSessions you use, in finally blocks

FROM:

  public void resetGroupMembers(final DynamicGroupDefinition definition) {
    try {
      final GrouperSession session = GrouperSession.start(
          SubjectFinder.findRootSubject(), false);
      GrouperSession.callbackGrouperSession(session,
          new ResetGroupMembersCallback(this, definition.getGroupUUID()));
    } catch (SessionException e) {
      LOGGER.error(e, e);
    }
  }

TO:

  public void resetGroupMembers(final DynamicGroupDefinition definition) {
    GrouperSession session = null;
    try {
      session = GrouperSession.start(SubjectFinder.findRootSubject(), false);
      GrouperSession.callbackGrouperSession(session,
          new ResetGroupMembersCallback(this, definition.getGroupUUID()));
    } catch (SessionException e) {
      LOGGER.error(e, e);
    } finally {
      GrouperSession.stopQuietly(session);
    }
  }

############################################

3. Try again and let me know how it goes...


Thanks!
Chris


> -----Original Message-----
> From: Chris Hyzer
> Sent: Tuesday, August 11, 2009 12:16 PM
> To: 
> '';
>  Grouper Dev
> Subject: RE: [grouper-dev] Strange error while creating groups
> 
> One problem is in ehcache:
> 
>         for (int i = 0; i < ALL_CACHE_MANAGERS.size(); i++) {
>             CacheManager cacheManager = (CacheManager)
> ALL_CACHE_MANAGERS.get(i);
> 
> I think if a cache is removed in another thread (GC) between those
> lines, then you can the out of bounds exception...  I looked in the
> latest ehcache, and the implementation is a little different as far as
> multi-threaading, but this bug still is there.
> 
> I opened a bug report with ehcache:
> http://sourceforge.net/tracker/?func=detail&aid=2835670&group_id=93232&;
> atid=603559
> Either way, we should upgrade to the latest soon.
> 
> I noticed that GrouperSession does not close caches on "stop()", but
> only on finalize() (during garbage collection).  So the caches will
> bulk up until garbage collection...  so I think a medium term solution
> is to close caches on GrouperSession.stop().  If there aren't 200 cache
> managers, this is less likely to happen...
> 
> An easy solution that might help is to synchronize the cache creation
> on the same resource that the cache remove in ehcache is
> synchronized...
> 
> Can you confirm you are on the 1.4 branch, and I can try to implement
> something there that should fix this?
> 
> Another solution which shouldn't be necessary is to have a static root
> grouper session (but still do the callbacks)....
> 
> In other words, something like this
> 
> FROM:
> 
>     /**
>      * Creates a group if it does not exist, removes all its members
> otherwise .
>      * @param definition The definition of the group.
>      * @see
> org.esco.dynamicgroups.dao.grouper.IGroupsDAOService#resetGroupMembers(
> DynamicGroupDefinition)
>      */
>     public void resetGroupMembers(final DynamicGroupDefinition
> definition) {
>         try {
>             final GrouperSession session =
> GrouperSession.start(SubjectFinder.findRootSubject(), false);
>             GrouperSession.callbackGrouperSession(session,
>                     new ResetGroupMembersCallback(this,
> definition.getGroupUUID()));
>         } catch (SessionException e) {
>             LOGGER.error(e, e);
>         }
>     }
> 
> TO:
> 
>     private final static GrouperSession rootSession = null;
> 
>     private static GrouperSession rootSession() {
>       if (rootSession == null) {
>         try {
>           rootSession =
> GrouperSession.start(SubjectFinder.findRootSubject(), false);
>         } catch (SessionException e) {
>             LOGGER.error(e, e);
>         }
>       }
>       return rootSession;
>     }
> 
>     /**
>      * Creates a group if it does not exist, removes all its members
> otherwise .
>      * @param definition The definition of the group.
>      * @see
> org.esco.dynamicgroups.dao.grouper.IGroupsDAOService#resetGroupMembers(
> DynamicGroupDefinition)
>      */
>     public void resetGroupMembers(final DynamicGroupDefinition
> definition) {
>         try {
>             GrouperSession.callbackGrouperSession(rootSession(),
>                     new ResetGroupMembersCallback(this,
> definition.getGroupUUID()));
>         } catch (SessionException e) {
>             LOGGER.error(e, e);
>         }
>     }
> 
> > -----Original Message-----
> > From: Arnaud Deman 
> > [mailto:]
> > Sent: Tuesday, August 11, 2009 10:34 AM
> > To: Grouper Dev
> > Subject: [grouper-dev] Strange error while creating groups
> >
> > Hello,
> >
> > I am trying to stress test an extension of grouper that I have
> written
> > and of course ... it crashes :-( .
> >
> > It is no deterministic : this time it occurred after creating more
> than
> > 4500 groups but sometime it happens after 300 group creations.
> > Initially I thought it was because of a bad use  of the  grouper
> > sessions but  I  have corrected everything to use  the  callback
> > mechanism.
> >
> > I have joined the stack and the instruction which generates the
> > exception is  :
> >
> > (in the method resetGroupMembersInternal)
> >
> > @SuppressWarnings("unchecked")
> >  final Set<Member> members = group.getImmediateMembers();
> >
> > If someone has an idea of a direction to investigate, I would really
> > appreciate because I am not very inspired...
> >
> >
> >
> > Thanks,
> > Arnaud.
> >
> >
> > --
> >
> > Arnaud Deman
> > GIP RECIA
> > Parc d'activités les Aulnaies
> > 151 rue de la Juine - 45160 OLIVET
> > Tel : 02 38 42 14 69
> >