APAR status
Closed as program error.
Error description
A NullPointerException from the
SelectionManager.popServerForInvocation method is thrown under
very heavy workloads.
Local fix Problem summary
****************************************************************
* USERS AFFECTED: WebSphere Application Server users of *
* workload management, or WLM *
****************************************************************
* PROBLEM DESCRIPTION: A NullPointerException or *
* ConcurrentModificationException is *
* thrown from either the *
* SelectionManager or PMIManager during *
* very heavy workloads *
****************************************************************
* RECOMMENDATION: *
****************************************************************
Under heavy workloads, a NullPointerException or
ConcurrentModificationException is thrown from a
WeakHashmap object in the Workload Management code.
The exception may look something like this:
Root exception is java.util.ConcurrentModificationException:
concurrent access to HashMap attempted by Thread Thread-7,5,
at java.util.HashMap.onExit(HashMap.java:175)
at java.util.HashMap.rehash(HashMap.java:347)
at java.util.HashMap.put(HashMap.java:418)
at java.util.WeakHashMap.put(WeakHashMap.java:298)
at com.ibm.ws.wlm.client.selection.SelectionManager.
pushServerForInvocat
at com.ibm.ws.wlm.client.selection.SelectionManager.
getTarget(SelectionM
...
...
Problem conclusion
There were synchronization issues with a WeakHashmap
used by both the PMIManager and the SelectionManager
that needed to be resolved. In both classes, the issue
didn't surface unless the client was run on a very large
box.
Temporary fix
There is no temporary Fix. iFix has been sent to customer
to verify that it resolves the issue at hand.
Comments
APAR information |
APAR number |
PQ80782 |
Reported component name |
WAS BASE 5.0 |
Reported component ID |
5630A3600 |
Reported release |
00W |
Status |
CLOSED PER |
PE |
NoPE |
HIPER |
NoHIPER |
Special Attention |
NoSpecatt |
Submitted date |
2003-11-11 |
Closed date |
2003-12-19 |
Last modified date |
2003-12-19 |
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Modules/Macros
Publications Referenced
Applicable component levels |
R003 PSY |
UP |
R00A PSY |
UP |
R00H PSY |
UP |
R00I PSY |
UP |
R00P PSY |
UP |
R00S PSY |
UP |
R00W PSY |
UP |
R103 PSY |
UP |
R10A PSY |
UP |
R10H PSY |
UP |
R10I PSY |
UP |
R10P PSY |
UP |
R10S PSY |
UP |
R10W PSY |
UP |
|