Re: MySQL with KSE -- Unstable?

On Tue, 3 Feb 2004, Kris Gale wrote:

> I've given MySQL on KSE a couple of tries in production, and I've
> run into a problem where threads seem to build up after an hour
> or so, depending on load.
> 
> The first time I tried it, we were maintaining a load of about 600
> threads and 300 queries/second and lasted about three hours
> before the thread count went through the roof and MySQL became
> unresponsive.
> 
> The second time, we were sustaining a load of 1300 threads and
> 600 queries/second.  This only lasted about 30 minutes.
> 
> Each time, upon attempting to restart MySQL without first shutting
> down the web cluster that was using it, the server rebooted.
> I'm not sure if this was because MySQL got flooded with reconnect
> requests, and the machine crashed trying to start up threads
> that quickly.
> 
> Any ideas?  Has anyone else had success with MySQL on 5.2
> with KSE in high-load environments?

It would help if you could give us some way to reproduce
this.  How you configure/install MySQL, what scripts to
run to generate the queries, etc.  I've not really used
MySQL too much, so don't assume I know anything ;-)

Also, you may have to increase kern.threads.max_threads_per_proc
if you have a lot of threads stuck in the kernel.

-- 
Dan Eischen