[rabbitmq-discuss] RabbitMQ odd behaviour

Mon Jun 23 23:57:51 BST 2008

Dave,

On Mon, Jun 23, 2008 at 4:30 PM,  <David.Corcoran at edftrading.com> wrote:
> I've been seeing some odd slow downs in RabbitMQ and I think it's also
> possible to see them with unmodified ProducerMain and ConsumerMain. My
> producers managed to publish about 18k messages/second but my consumers
> only managed to read at about 1k messages/second. To replicate this run
> ProducerMain and ConsumerMain at the same time and you get a good rate of
> about 17K messages/second. But if you run ProducerMain until it finishes
> (it gets 18K/second) and then run ConsumerMain, ConsumerMain only gets
> about 1K messages/second.
>
> Is this normal or is there something odd going on?

No I don't think this is normal. Using a the Apple 1.5.0.13 JDK on OSX
10.5.3 with Erlang R12B-3 on the same machine, I get 10K in and 25K
out when running them one after another. When I run them concurrently,
I get an even 7.5K in and out. I can have a look to see what
difference it makes on a Linux machine tomorrow, but unfortunately I
don't have an answer today. Can you maybe give some more details about
how you are running the tests?

> java clients
> RabbitMQ 1.3.0-1
> Ubuntu 8.04 amd64 with 4GB RAM
> Erlang 1:11.b.5dfsg-11
> OpenJDK 1.6.0_06-b02 64-bit

Just out of interest's sake, and I don't think this is causal, but
does it make any difference if you use R12B-3 instead of R11B-5? You
don't necessarily need root access to install this, if you set the
prefix-dir to be somewhere in your own user's directory when building
Erlang. Any questions, just ask.

HTH,

Ben