Re: Performance problem. Could it be related to 8.3-beta4?

On Jan 6, 2008 1:46 PM, Clodoaldo <clodoaldo(dot)pinto(dot)neto(at)gmail(dot)com> wrote:
> 2008/1/6, Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>:
>
> > On Jan 6, 2008 5:06 AM, Clodoaldo <clodoaldo(dot)pinto(dot)neto(at)gmail(dot)com> wrote:
> > >
> > > Then I rebuilt and reinstalled postgresql with the xlog_seg_size set
> > > to the default 16MB and did initdb. Now the time is 7,642 sec.
> > >
> > > I'm lost. It looks like 1GB xlog_seg_size is indeed faster than 16MB
> > > but again it is slower than the production server which uses the
> > > default xlog_seg_size.
> >
> > How fast was it the second time you ran it?
>
> You mean the new server with 16MB xlog_seg_size? Yes, I did run it
> twice and both took about the same time. In all tests (all
> configurations) I did an analyze before running so I think that is the
> real time.

OK, to eliminate the chance that it's sick hardware, I would suggest
installing 8.2.5 with exactly the same settings and build (as much as
possible) and see how that works. If it's still slow, I would suspect
the hardware is making the difference and investigate that first.
Once you get even performance from 8.2.5 on both sets of hardware,
then you can make a valid comparison with 8.3b4. Unless you've already
done that... then I don't have a clue what to do...