Re: New and confuse - WebSphere Express 6.1 and JVM on V5R4

["Dean, Robert" <rdean@xxxxxxxxxxxx>]

1) The current is WebSphere Express 7.0
2) WebSphere 7.0 uses JDK 1.6.  WebSphere 6.1 uses JDK 1.5.
3) As long as your application is written in Java, it should run on any certified JVM.
4) The classic JVM is based on Sun code and uses 64-bit pointers.  It's older technology that is slower, and the 64-bit pointers take up more memory.  The 32-bit JVM is a large performance pickup in terms of both CPU usage and memory usage.  The interesting thing is that with IBM i 6.1, there is a new 64-bit JVM.  Supposedly when used with WebSphere 7.0, it uses pointer compression to reduce the memory usage required because of 64-bit addressing.  That just about eliminates the advantage of running a 32-bit JVM.

-----Original Message-----
From: web400-bounces@xxxxxxxxxxxx [mailto:web400-bounces@xxxxxxxxxxxx] On Behalf Of Lim Hock-Chai
Sent: Thursday, March 19, 2009 12:28 PM
To: Web Enabling the AS400 / iSeries
Subject: [WEB400] New and confuse - WebSphere Express 6.1 and JVM on V5R4

I'm a Project Management that has primary been working on the RPG side
of thing.  I just being assigned to temporary manage our web team in
helping them move the current application server from jBOSS to websphere
Express.  The primary reason for this move is because we are currently
using a very old version of jBOSS which is currently running our web
team's applications using classic JVM 1.4.  The ultimate goal is to move
it to the newest support version of Websphere Express and JVM on V5R4.
Below are some questions that I seems to not able to Google out:
 
1) Is Websphere Express 6.1 the latest available version for V5R4?
2) Is WebSphere Express written in java?  If so, how can I figure out
what version of JVM it is using?
3) Can our application that will be running in the Websphere Express run
in any version of supported JVM on V5R4?  (Independent of what WebSphere
Express is using (Assuming that Express is written in java)?
4) What is the different between the Classic JVM and IBM(r) Technology
for Java(tm) JVM?
 
Thanks