Re: Tuning PostgreSQL

So where can I set the noatime & data=writeback variables? They are not
PostgreSQL settings, but rather Linux settings, right? Where can I find
these?

Kind regards,
Alexander Priem.


----- Original Message -----
From: "Shridhar Daithankar" <shridhar_daithankar@persistent.co.in>
To: <pgsql-performance@postgresql.org>
Sent: Monday, July 21, 2003 12:31 PM
Subject: Re: [PERFORM] Tuning PostgreSQL


> On 21 Jul 2003 at 18:09, Ang Chin Han wrote:
>
> > Shridhar Daithankar wrote:
> > > On 21 Jul 2003 at 11:23, Alexander Priem wrote:
> >
> > >>I use ext3 filesystem, which probably is not the best performer, is
it?
> > >
> > > No. You also need to check ext2, reiser and XFS. There is no agreement
between
> > > users as in what works best. You need to benchmark and decide.
> >
> > Need? Maybe I'm a bit disillusioned, but are the performances between
> > the filesystems differ so much as to warrant the additional effort?
> > (e.g. XFS doesn't come with Red Hat 9 -- you'll have to patch the
> > source, and compile it yourself).
>
> Well, the benchmarking is not to prove which filesystem is fastest and
feature
> rich but to find out which one suits your needs best.
>
> > Benchmarking it properly before deployment is tough: are the test load
> > on the db/fs representative of actual load? Is 0.5% reduction in CPU
> > usage worth it? Did you test for catastrophic failure by pulling the
> > plug during write operations (ext2) to test if the fs can handle it? Is
> > the code base for the particular fs stable enough? Obscure bugs in the
fs?
>
> Well, that is what that 'benchmark' is supposed to find out. Call it pre-
> deployment testing or whatever other fancy name one sees fit. But it is a
must
> in almost all serious usage.
>
> > For the record, we tried several filesystems, but stuck with 2.4.9's
> > ext3 (Red Hat Advanced Server). Didn't hit a load high enough for the
> > filesystem choices to matter after all. :(
>
> Good for you. You have time at hand to find out which one suits you best.
Do
> the testing before you have load that needs another FS..:-)
>
> Bye
>  Shridhar
>
> --
> It would be illogical to assume that all conditions remain stable. --
Spock, "The Enterprise" Incident", stardate 5027.3
>
>
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