pSeries, AIX, WAS and the JVM

I've been swamped at work so have had little time for this blog, but have still spent some time digging into how WAS works.

Some articles on how the Java5 JVM works clarify some of my earlier findings. See

http://www.ibm.com/developerworks/java/library/j-ibmjava4/

and

http://www.ibm.com/developerworks/java/library/j-ibmjava1.html

I have used this information to investigate WAS and how it uses the com.ibm.cds_1.0.0.jar classloader from the Eclipse plugins to work with shared classes. I will publish some results here soon.

Note also that the Java6 JVMs are ow on their way from IBM:

https://www14.software.ibm.com/iwm/web/cc/earlyprograms/ibm/java6/index.shtml

In digging into how the JVM works I unjarred (jar xvf) core.jar and src.jar that come with the Java5 JVM shipped with WAS. Within core.jar there is a class called ProcessorCapacityNotification that it appears looks out for the changes in capacity that would be seen with dynamic LPAR'ing. The next challenge is to work out if it does this effectively, and then to find out if WAS responds to this information.

See you soon!

Colin