Java agent WebSphere class cache behaviour
Article ID: 112755
Updated On:
Products
CA Application Performance Management Agent (APM / Wily / Introscope)
INTROSCOPE
Issue/Introduction
IBM WebSphere employs a method of class caching for performance reasons, loading bytecode into a cache persisted on disk that can be shared by mutliple applications using the same JDK.
Because the APM Java Agent performs bytecode instrumentation, references to the Java Agent code are also stored in this cache
When updating the Java Agent version, the cached version of the agent's code may have been changed.
This can lead to conflicts causing problems with both the agent's and monitored application's behaviour.
Because the APM Java Agent performs bytecode instrumentation, references to the Java Agent code are also stored in this cache
When updating the Java Agent version, the cached version of the agent's code may have been changed.
This can lead to conflicts causing problems with both the agent's and monitored application's behaviour.
Environment
Release:
Component: APMISP
Component: APMISP
Resolution
The recommendation would be to clear the WebSphere class cache after every change to the agent code, particularly where upgrading the version, but also advisable where applying individual fixes
Additional Information
IBM information on clearing WebSphere class caches:
http://www-01.ibm.com/support/docview.wss?uid=swg21607887
http://www-01.ibm.com/support/docview.wss?uid=swg21607887
Feedback
Yes
No
Powered by
