Re: [eclipselink-users] Are transaction-scoped persistence contexts cohe

[James Sutherland <jamesssss@xxxxxxxxx>]

I doubt whether this is actually possible.  Definitely if you are using local
SessionBeans I can't see how it is possible.  If you are using remote
SessionBeans I'm not sure it is possible or even supported by WLS or WAS. 
Are you seeing this behavior, or having this issue?

If you somehow did get into this scenario, then the other server is not
going to see the non-flushed changes made on the other server if both are
using the same persistence context.  This would only be an issue if the two
sets of changes overlap.  But I have never seen this occur, and if it did,
would think this would be the least of your issues.

I would always recommend using local SessionBeans on the server.


Staub, Edward wrote:
> 
> The title just about asks it all.
> 
> I'm considering using EclipseLink in a clustered, high-throughput
> application that runs on both WebLogic and WebSphere.  I know little.
> 
> AFAICT, in a clustered environment, stateless session beans from the same
> EAR (or jar within) can potentially be called within the same transaction
> from multiple servers.  "Transactional affinity" prefers to run all EJBs
> within a transaction from the same server - but does not guarantee it
> -again, AFAICT.
> 
> Consider a heavy-load case where a transaction with an associated
> persistence context starts on one server, then switches to another when a
> REQUIRES-transaction SLSB is called while the first server is saturated in
> some way.  The second server won't see the uncommitted updates made on the
> first server's unit of work.  Is this handled by EclipseLink?  If not,
> does anyone have a workaround?
> 
> Thanks in advance
> 
> -          Ed Staub
> 
> 
> 


-----
http://wiki.eclipse.org/User:James.sutherland.oracle.com James Sutherland 
http://www.eclipse.org/eclipselink/
 EclipseLink ,  http://www.oracle.com/technology/products/ias/toplink/
TopLink 
Wiki:  http://wiki.eclipse.org/EclipseLink EclipseLink , 
http://wiki.oracle.com/page/TopLink TopLink 
Forums:  http://forums.oracle.com/forums/forum.jspa?forumID=48 TopLink , 
http://www.nabble.com/EclipseLink-f26430.html EclipseLink 
Book:  http://en.wikibooks.org/wiki/Java_Persistence Java Persistence 
-- 
View this message in context: http://old.nabble.com/Are-transaction-scoped-persistence-contexts-coherent-in-clusters--tp29905797p30001276.html
Sent from the EclipseLink - Users mailing list archive at Nabble.com.