Thanks so much for your response. We use transacted sessions with
non-persistent delivery. Prefetch size is 1 and every message is same size
On Sat, Oct 15, 2016 at 2:59 AM, Rob Godfrey <rob.j.godf...@gmail.com>
> Hi Ramyan,
> this is interesting... in our testing (which admittedly didn't cover the
> case of this many queues / listeners) we saw the 6.0.x broker using less
> CPU on average than the 0.32 broker. I'll have a look this weekend as to
> why creating the listeners is slower. On the dequeing, can you give a
> little more information on the usage pattern - are you using transactions,
> auto-ack or client ack? What prefetch size are you using? How large are
> your messages?
> On 14 October 2016 at 23:46, Ramayan Tiwari <ramayan.tiw...@gmail.com>
> > Hi All,
> > We have been validating the new Qpid broker (version 6.0.4) and have
> > compared against broker version 0.32 and are seeing major regressions.
> > Following is the summary of our test setup and results:
> > *1. Test Setup *
> > *a). *Qpid broker runs on a dedicated host (12 cores, 32 GB RAM).
> > *b).* For 0.32, we allocated 16 GB heap. For 6.0.6 broker, we use 8GB
> > heap and 8GB direct memory.
> > *c).* For 6.0.4, flow to disk has been configured at 60%.
> > *d).* Both the brokers use BDB host type.
> > *e).* Brokers have around 6000 queues and we create 16 listener
> > sessions/threads spread over 3 connections, where each session is
> > to 3000 queues. However, messages are only enqueued and processed from 10
> > queues.
> > *f).* We enqueue 1 million messages across 10 different queues (evenly
> > divided), at the start of the test. Dequeue only starts once all the
> > messages have been enqueued. We run the test for 2 hours and process as
> > many messages as we can. Each message runs for around 200 milliseconds.
> > *g).* We have used both 0.16 and 6.0.4 clients for these tests (6.0.4
> > client only with 6.0.4 broker)
> > *2. Test Results *
> > *a).* System Load Average (read notes below on how we compute it), for
> > 6.0.4 broker is 5x compared to 0.32 broker. During start of the test
> > we are not doing any dequeue), load average is normal (0.05 for 0.32
> > and 0.1 for new broker), however, while we are dequeuing messages, the
> > average is very high (around 0.5 consistently).
> > *b). *Time to create listeners in new broker has gone up by 220%
> > to 0.32 broker (when using 0.16 client). For old broker, creating 16
> > sessions each listening to 3000 queues takes 142 seconds and in new
> > it took 456 seconds. If we use 6.0.4 client, it took even longer at 524%
> > increase (887 seconds).
> > *I).* The time to create consumers increases as we create more
> > listeners on the same connections. We have 20 sessions (but end up using
> > around 5 of them) on each connection and we create about 3000 consumers
> > attach MessageListener to it. Each successive session takes longer
> > (approximately linear increase) to setup same number of consumers and
> > listeners.
> > *3). How we compute System Load Average *
> > We query the Mbean SysetmLoadAverage and divide it by the value of MBean
> > AvailableProcessors. Both of these MBeans are available under
> > java.lang.OperatingSystem.
> > I am not sure what is causing these regressions and would like your help
> > understanding it. We are aware about the changes with respect to
> > model in the new broker, are there any design docs that we can refer to
> > understand these changes at a high level? Can we tune some parameters to
> > address these issues?
> > Thanks
> > Ramayan