From: | Rolf Østvik <rolfostvik(at)yahoo(dot)no> |
---|---|
To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | pgsql-performance(at)postgresql(dot)org |
Subject: | Re: Worse perfomance on 8.2.0 than on 7.4.14 |
Date: | 2007-01-01 15:19:05 |
Message-ID: | 20070101151905.55545.qmail@web26309.mail.ukl.yahoo.com |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-performance |
--- Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> skrev:
> Rolf =?iso-8859-1?q?=D8stvik?= <rolfostvik(at)yahoo(dot)no>
> writes:
> > I have a simple query which uses 32ms on 7.4.14
> and 1015ms on 8.2.0.
>
> There's something awfully strange about that 8.2
> plan --- if it knew
> that it'd have to scan all of uut_result_subset
> (which it should have
> known, if the stats were up-to-date),
I can't really see the need for it to do an sequence
scan, but that is me not knowing how things work.
>why did it use
> an indexscan
> rather than a seqscan? Are you sure you haven't
> tweaked any parameters
> you didn't tell us about, such as setting
> enable_seqscan = off?
I haven't touched enable_seqscan.
It could be that i have forgotton to tell you about a
parameter i have tweaked, but i doubt it.
Best regards
Rolf Østvik
__________________________________________________
Bruker du Yahoo!?
Lei av spam? Yahoo! Mail har den beste spambeskyttelsen
http://no.mail.yahoo.com
From | Date | Subject | |
---|---|---|---|
Next Message | Tom Lane | 2007-01-01 23:30:27 | Re: Worse perfomance on 8.2.0 than on 7.4.14 |
Previous Message | Rolf Østvik | 2007-01-01 15:14:14 | Re: Worse perfomance on 8.2.0 than on 7.4.14 |