| From: | Cott Lang <cott(at)internetstaff(dot)com> |
|---|---|
| To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
| Cc: | pgsql-general(at)postgresql(dot)org |
| Subject: | Re: Problem with query plan |
| Date: | 2004-10-22 23:38:57 |
| Message-ID: | 1098488337.3551.80.camel@localhost |
| Views: | Whole Thread | Raw Message | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
On Fri, 2004-10-22 at 14:19, Tom Lane wrote:
> Cott Lang <cott(at)internetstaff(dot)com> writes:
> > sort_mem = 8192
> > random_page_cost = 2
> > effective_cache_size = 3932160
>
> effective_cache_size 30Gb ? Seems a tad high ;-)
It's a 32GB machine with nothing else running on it except PG, buffers
hover around 31GB :)
> However, I set up a dummy test case on 7.4.5 and don't see any overflow.
> Can you try this exact test case and see if you get a NAN?
I don't. After a bounce, I also can't repeat my original case; it now
returns 16.60.
Fiddling with the above values, only setting sort_mem absurdly large
easily causes NAN.
My guess is there was a wonky setting for sort_mem that disappeared
after I bounced.
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Mark Harrison | 2004-10-22 23:55:28 | combining two queries? |
| Previous Message | Tom Lane | 2004-10-22 23:11:52 | Re: ia64 hostname lookup problem |