Re: Is Linux 2.6.5 kernel good enough for production?

On Wed, 12 May 2004, Dirk Försterling wrote:

> Am 05/05/2004 03:03 PM schrieb Luiz Rafael Culik Guimaraes:
> >
> >>Do people think linux 2.6.5 is stable enough yet for a production
> >>PostgreSQL server?
> >
> > i´m using linux 2.6.5 with postgres 7.4.2 with out problem(conectiva linux
> > version 10)
>
> I'd like to add here, that I recently tried 2.6.5 / Postgres 7.4.2 and
> found out that overall system performance during database operations
> decreased dramatically.
>
> A series of queries that were usually done within about 30 minutes on
> Linux 2.4.25 / Postgres 7.4.2 took about 3 (three) hours on Linux 2.6.5
> with Postgres 7.4.2 on the same machine with the same configuration.
>
> While on Linux 2.4.25 the queries ran smoothly in background without
> impacting other activity, the responsiveness of the whole machine got
> so bad with 2.6.5 during the 3 hour query that simple http requests to
> an Apache server on the same machine repeatedly timed out.
>
> I still don't know WHY this happened, but I believe it may resolve as
> a configuration issue. Maybe Postgres, maybe the Linux kernel.

Which of the two 2.6 schedulers are you running?  It would seem the
pre-emptive schedule, while making for a better user experience on
workstations, is not as good as the deadline scheduler for things like
servers.