Hi @sumit047 . It looks like you are using “ack each message” mode, so my first guess around windowed/delayed publisher acknowledgements is wrong. Your logs show the app quitting after this one message… are you able to reproduce the same 12ms delay when publishing lots of messages in a row?
Having debug logging enabled might also slow things down a bit in your app, depending how many messages you’re publishing.
Is your JMS app using Persistent or Non-Persistent? If Persistent, then you can only have 1 published message “in-flight” at once. How far away is the broker that you’re publishing to, what is the RTT?