I set the optimizedAcknowledge flag in the consumer client to patch the knowledge for boosting performance by following the link below: http://open.iona.com/wiki/display/ProdInfo/FUSE+Message+Broker+Performance+Tuning+Guide
By setting the optimized Acknowledge, the performance do greatly improved from 14000 msgs/s to 20000 msgs/s. My testing enviroment has three machines: producer, consumer and broker are all in different machine and I am using ActiveMQ 5.0. For get above best result, I just use one producer and one consumer thread. Then I want to see how the performance changed when I improve the number of consumer threads. Since in my consumer code, the consumer does nothing except counting the number of messages received when be notified, so adding number of consumers, the performance may get down a little bit as my expectation. But the result make me surprised, below is the result (all using one producer): 1 consumer: ~20000/s 2 consumers: ~18000/s 3 consumers: ~1500/s 4 consuerms: ~500/s When I reset optimizedKnowledge flag, the result get back to normal: 1 consumer: ~15000/s 2 consumers: ~14000/s 3 consumers: ~12000/s 4 consumers ~11000/s How optimizedKnowlwege flag affect the performance for threads so much. Any ideas? Thanks, Zao -- View this message in context: http://www.nabble.com/optimizedAcknowledge-flag-with-performance-issue-tp15641642s2354p15641642.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.