PI20914: NATIVE STORAGE LEAK WHEN SMF120 SUB-TYPE9 RECORDING TURNED ON.

Fixes are available

APAR status

Closed as program error.

Error description

High CPU, excessive GC, java.lang.OutOfMemoryError exceptions
seen in controller region when SMF recording is turned on for
SMF120 record subtype 9.

Local fix

avoid recording SMF-120 subtype9 data until  the official fix
is applied.

Problem summary

****************************************************************
* USERS AFFECTED:  All users of IBM WebSphere Application      *
*                  Server V8.0 and V8.5                        *
****************************************************************
* PROBLEM DESCRIPTION: A WebSphere Application Server for      *
*                      z/OS                                    *
*                      server using Asychronous Beans and      *
*                      with SMF 120 Subtype 9 CPU recording    *
*                      enabled receives a                      *
*                      java/lang/OutOfMemoryError in the       *
*                      Servant.                                *
****************************************************************
* RECOMMENDATION:                                              *
****************************************************************
When Work submitted to an Asynchronous Beans Work Manager is
executed, certain RAS information such as whether to record
SMF data is set onto the thread of execution.  When the Work
completes, this information is reset to a clean state.  This
works fine when the Work is executed on a thread in the Work
Manager's thread pool, however it is possible to submit Work
to run on the current thread by using the
com.ibm.websphere.asynchbeans.WorkManager.doWork API.  What
happens in this case is that after the Work completes and the
RAS information is reset, control is returned back to the
code that submitted the Work, but the RAS state is no longer in
effect.
When SMF 120 Subtype 9 CPU recording is enabled, this causes a
memory leak.  Certain objects that contain SMF data are created
prior to the doWork invocation.  When doWork returns and the
RAS state has been reset, the SMF objects are not cleaned up.
This will eventually lead to a
java/lang/OutOfMemoryError in the Servant.  Analysis of a heap
dump will show a large number of
com.ibm.ws390.sm.smf.SmfRequestTracker objects.

Problem conclusion

Code was fixed so that when doWork completes, the RAS state is
set back to what it was prior to the doWork call instead of to
a completely clean default state.

APAR PI20914 is currently targeted for inclusion in Fix Packs
8.0.0.10 and 8.5.5.4 of WebSphere Application Server.

Please refer to the Recommended Updates page for delivery
information:
http://www.ibm.com/support/docview.wss?rs=180&uid=swg27004980

In addition, please refer to URL:
http://www.ibm.com/support/docview.wss?rs=404&uid=swg27006970
for Fix Pack PTF information.

Temporary fix

Comments

APAR Information

APAR number
PI20914
Reported component name
WEBSPHERE FOR Z
Reported component ID
5655I3500
Reported release
800
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2014-06-26
Closed date
2014-07-08
Last modified date
2014-07-08

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 FOR Z
Fixed component ID
5655I3500

Applicable component levels

R800 PSY
UP

[{"Business Unit":{"code":"BU059","label":"IBM Software w\/o TPS"},"Product":{"code":"SS7K4U","label":"WebSphere Application Server for z\/OS"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"800","Line of Business":{"code":"LOB45","label":"Automation"}}]

Document Information

Modified date:
27 April 2022

Tips

PI20914: NATIVE STORAGE LEAK WHEN SMF120 SUB-TYPE9 RECORDING TURNED ON.

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

R800 PSY

Document Information

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