PK16552: MEMORY LEAK IN INVOCATION CACHE 06/01/05 PTF PECHANGE | |||||||||||||||||||||||||||||||||||||||||||
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![]() APAR status Closed as program error. Error description A memory leak has been found in the Invocation Cache which leads to an OutOfMemory situation. From the heapdump analysis it has been found that total number of com/ibm/ws/webcontainer/srt/WebAppInvoker live objects are more than expected. Expected maximum number of these objects is as calculated as per below: If, P = Thread pool Size C = invocation cache size Then, the max number of Cached WebAppInvoker objects should be the following: (2 * P + 1) * CLocal fix Setting the invocation cache size to zero will disable invocation cache functionality, and therefore eliminate the caching of WebAppInvoker objects. This can be set as follows: (1) In the administrative console, click the Application Server. (2) Click "Process Definition" under "Additional Properties". (3) Click the "Java Virtual Machine" under "Additional Properties". (4) Add the following argument in the Generic JVM arguments: -DinvocationCacheSize=0 (5) Click Apply to ensure that the changes are saved. (6) Stop and restart the application server.Problem summary **************************************************************** * USERS AFFECTED: All users of WebSphere Application Server * * V5.0 for z/OS * **************************************************************** * PROBLEM DESCRIPTION: Invocation cache causes a memory leak * * and OutofMemory exception. * * From the heapdump analysis, it was * * found that the total number of * * com/ibm/ws/webcontainer/srt/ * * WebAppInvoker live objects was * * more than expected. * **************************************************************** * RECOMMENDATION: * **************************************************************** Invocation caches are not released when associated transport threads are being destroyed. Hidden handles that hold up InvocationCache objects prevent JVM garbage collecting of an InvocationCache instance and its cached objects when a thread is being destroyed.Problem conclusion The code was modified to remove hidden handles that hold up InvocationCache. The fix also adds a thread pool listener that monitors thread activities within the pool. When a thread is being destroyed its invocation cache will be invalidated and released thus preventing memory leaks from invocation cache instances. APAR PK16552 is associated with SERVICE LEVEL W502038 of WebSphere Application Server V5.0 for z/OS.Temporary fix Comments
APAR is sysrouted FROM one or more of the following: PK12027 APAR is sysrouted TO one or more of the following: PK17423 Modules/Macros
Publications Referenced
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Document Information |
Current web document: swg1PK16552.html
Product categories: Software > Application Servers >
Distributed Application & Web Servers > WebSphere Application
Server for z/OS
Operating system(s):
Software version: 500
Software edition:
Reference #: PK16552
IBM Group: Software Group
Modified date: Feb 2, 2006
(C) Copyright IBM Corporation 2000, 2009. All Rights Reserved.