PK76467: MEMORY LEAK DUE TO HANDLELIST OBJECTS NOT BEING REMOVED FOR ENTITY BEANS

Fixes are available

APAR status

Closed as program error.

Error description

Problem: System runs out of memory with
com/ibm/ejs/j2c/HandleList objects
not being made available for garbage collection.

The reason for the leaks is the Enterprise JavaBeans Container
is not properly handling a specific case and the HandleList
object is not made available for garbage collection.

Local fix

Problem summary

****************************************************************
* USERS AFFECTED:  All users of IBM? WebSphere? Application    *
*                  Server V6.0.2, V6.1.0, Feature Pack for     *
*                  Enterprise JavaBeans 3.0, and V7.0.0.       *
*                                                              *
****************************************************************
* PROBLEM DESCRIPTION: HandleList objects cause a memory       *
*                      leak when Entity Beans are accessed     *
*                      in a 'reentrant' manner.                *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
When a user accesses their Entity Beans in
a 'reentrant' manner (as defined by the Enterprise JavaBeans
Specification), some com/ibm/ejs/j2c/HandleList objects
are not removed, and thus not garbage collected.  Accessing
Entity Beans in a 'reentrant' manner is legal unless they are
defined to not be 'reentrant'.  The scenario in which
HandleList object will leak is as follows: a user calls a
remote or local method ('method1') on their Entity Bean
('EB1').  From within this method, the user then makes a
'reentrant' call by calling another remote or local method
('method2'), on the SAME 'EB1' instance.  Note that a separate
HandleList object will be created for the execution of each
method.  When the method 'method2' completes, the Enterprise
JavaBeans Container cleans up the HandleList objects created
for 'method2', as it should, but mistakenly "marks" internal
state to indicate that all HandleList objects have been
removed for the bean instance 'EB1'.  As such, when 'method1'
completes, the Enterprise JavaBeans Container does not clean
up the HandleList objects created for 'method1' because the
Enterprise JavaBeans Container *thinks* it has already cleaned
up all HandleList object for the bean instance 'EB1' by virtue
of the incorrect internal state.  In this case, the Enterprise
JavaBeans internals think there is nothing to clean up.  That
is, the Enterprise JavaBeans Container is not accounting for
this reentrant case when it comes to HandleList clean up.

Problem conclusion

With this fix, the Enterprise JavaBeans container will ensure
that a HandleList object is cleaned up when a method exits
if the HandleList object was created in response to the
execution of the method.

The fix for this APAR is currently targeted for
inclusion in Service Levels (Fix Packs) 6.0.2.35, 6.1.0.23,
Enterprise JavaBeans 3.0 Feature Pack Fix Pack 23
(6.1.0.23), and 7.0.0.5 of WebSphere Application Server
versions 6.0.2, 6.1.0, and 7.0.0.
Please refer to the recommended updates page for delivery
information:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980

Temporary fix

Comments

APAR Information

APAR number
PK76467
Reported component name
WEBSPHERE APP S
Reported component ID
5724J0800
Reported release
61W
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2008-11-25
Closed date
2008-12-18
Last modified date
2008-12-18

APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:

Fix information

Fixed component name
WEBSPHERE APP S
Fixed component ID
5724J0800

Applicable component levels

R60A PSY
UP
R60H PSY
UP
R60I PSY
UP
R60P PSY
UP
R60S PSY
UP
R60W PSY
UP
R60Z PSY
UP
R61A PSY
UP
R61H PSY
UP
R61I PSY
UP
R61P PSY
UP
R61S PSY
UP
R61W PSY
UP
R61Z PSY
UP
R700 PSY
UP

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SSEQTP","label":"WebSphere Application Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"6.1","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
29 December 2021

Tips

PK76467: MEMORY LEAK DUE TO HANDLELIST OBJECTS NOT BEING REMOVED FOR ENTITY BEANS

Fixes are available

Subscribe

APAR status

Closed as program error.

Error description

Local fix

Problem summary

Problem conclusion

Temporary fix

Comments

APAR Information

APAR number

Reported component name

Reported component ID

Reported release

Status

PE

HIPER

Special Attention

Submitted date

Closed date

Last modified date

APAR is sysrouted FROM one or more of the following:

APAR is sysrouted TO one or more of the following:

Fix information

Fixed component name

Fixed component ID

Applicable component levels

R60A PSY

R60H PSY

R60I PSY

R60P PSY

R60S PSY

R60W PSY

R60Z PSY

R61A PSY

R61H PSY

R61I PSY

R61P PSY

R61S PSY

R61W PSY

R61Z PSY

R700 PSY

Document Information

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