MQSeries.net :: View topic - WTX map node not working correctly in multi threaded scenari

sanjoo · Posted: Mon Jan 28, 2013 5:32 am Post subject:

OS : AIX 5.3
WMB 6.1.0.4
WTX 8.2.0.4

Problem description: In multi threaded message flow, we use WTX node with following settings -
MapAudit > AuditLocation > File > FileName > Unique
MapTrace > TraceLocation > File > FileName > Unique
WorkSpace > File > WorkFilePrefix > Unique
Cache map property checked

Message flow has 10 instances on it and meant to process bulk files.
When 3 files are played concurrenetly, then 2 threads runs successfully. However for one thread, when control is propagated to WTX node nothing happens. It neither goes to out terminal nor to failure. Control comes back to next statement after propagate and thread is closed as if processing was successful and file is lost.

Obesrvation:
For two concurrent files, no issue observed.
Never ever since last broker deployment was done, 3 concurrent files were run. ie on the very first run of 3 concurrent files, above issue is noticed.

Our theory:
When we deploy message flow with 10 additioanl instances and WTX cache map checked, 10 copies of map are created in memory one per additional thread and these copies are always alive irrespective of thread life time.
We saw several 2 concurrent file runs before this issue popped up but never 3 concurrent file scenario. Does this mean that first 2 cached map instances were saved from garbage collectiion just because they were used more frequently and 3rd onward map instances were removed from cache by garbage collector.
If due to above reason, map is not loaded when thread tries to use it, exception will not be generated as per known APAR PM32225. I am not sure if our analysis is correct but any clues will be highly appreciated. We have raised a PMR anyway.

BROKER WHEN CACHE MAP IS ENABLEDPM32225: WTX MAP NODE FAILURE TO LOAD A MISSING MAP DOES NOT REPORT EXCEPTION TO MESSAGE

Error description
A WTX Map node failure to load a missing map does not report an
exception to Message Broker when the "Cache map" property is
enabled, which prevents the message flow from being able to
perform normal exception handling of the message.
Problem conclusion
The code has been corrected and an exception is reported if the
map cannot be loaded.

Delivered in:
8.2.0.6, 8.3.0.4

Thanks
Sanjoo
_________________
Sanjoo

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