MQSeries.net :: View topic - Is the Environment structure thread safe?

klingelb · Posted: Fri Oct 11, 2002 1:27 am Post subject:

I have deployed a message flow and specified 100 additional intances.
I need a global variable that is thread safe that I can store a simple counter in. So that each message that comes through the flow
increments this counter by one. I tried storing this counter in a DB2
DB, but the read operation is not blocking so multiple thread read the counter at the same time...not good. I also don't want to make the whole flow transactional, because that would defeat the purpose of bumping up the additional instance count on the message flow. I tried the following:

IF Environment.newtrxnId IS NULL then
SET Environment.newtrxnId = 1;
else
SET Environment.newtrxnId = CAST(Environment.newtrxnId AS INTEGER) + 1;
end IF;

But I found that Environment must not be thread safe because all my newtrxnId were equal to 1. Any Ideas?