MQSeries.net :: View topic - Performance hit using Pub/Sub for event messages vs. Dispatc

aspre1b · Posted: Mon Sep 22, 2008 1:20 am Post subject:

I'm producing a new flow that will process event messages from System A, ultimately destined for System B. There is a small chance (although unlikely) that the event messages could be utilised by System C in the future.

To provide the maximum flexibility I wish to put the event messages through the pub/sub engine of the broker. My only concern is the number of event msgs that may have to be processed, and the overhead the pub/sub engine adds over a simple dispatcher model.

I did some prototyping with 20k msgs and put these to:
1. an event dispatcher that eventually published the msg, a queue serviced by System B subscribed to the topic.
2. an event dispatcher that put to a queue serviced by System B

Pub / Sub of 20k messages - 1k to one topic, 19k to another topic.
Run 1 - 1min 29s
Run 2 - 1min 30s
Run 3 - 1min 33s

Putting to a queue directly - 20k messages - 1k to one queue, 19k to another queue.
Run 1 - 1min 11s
Run 2 - 1min 11s
Run 3 - 1min 13s

Using the Windows performance tool, I tested the CPU, I/O and memory utilisation during the time when the event messages were being distributed via the Pub/Sub engine and directly to a local queue. Apart from the time, the results were very much the same:
CPU ran at 100% for the period of when the messages were being distributed.
Memory averaged around 30% for both tests.
File I/O showed occasional spikes, but mainly ranged between 20% and 30% for both tests.

NB:It took between 36 and 41 seconds to load the input queue

Is there anything else I should consider before going down the pub/sub route? If this performance question has been addressed before, my apologises, but I couldn't find it.

MQ Version 5 CSD 11
Broker 5 CSD 8 (AIX in production)