We are using Websphere 5.0.2 Network deployment edition for our internal J2EE project (a high speed message switching application). We are primarily using Message driven beans and Local Stateless Session beans - we are not using entity beans at all. All our transactions are mainly XA oriented (we use container managed transactions, not JTA explicitly). Our database is DB2 8.1 UDB on pSeries (even websphere runs on the pSeries). Our messaging engine is MQ 5.3. We use type 4 JDBC drivers for DB2.
What I would like to know is whether the Websphere 5 Transaction manager has any in-built parallelism for XA transatctions e.g., suppose my XA transaction writes to an MQ queue and also writes to a DB2 table (in that order).
Then, does the WAS 5 TM internally do these individual operations in parallel or are they sequential ? If sequential, is there any way (say passing cmd line options to the WAS JVM or through some options in the WAS 5 console) to make the WAS 5 TM manager work in 'parallel' mode.
Would there be any downside/unpleasant side effect of doing so? Will it also make the transaction faster (my guess is it would be faster).
I was prompted by this request after viewing a thread on XA transactions recently on the serverside.com forum, where there were discussions about parallelism support in current J2EE app server Transaction managers?
There are claims that Weblogic does this intrinsically (without any extra options), so I am curious to know whether this is also a feature of the WAS 5 transaction manager.