Re: 7.3.2 vs 7.1.2 - Mailing list pgsql-performance

From Eugene Fokin
Subject Re: 7.3.2 vs 7.1.2
Date
Msg-id 20030520153348.GA30541@solvo.ru
Whole thread Raw
In response to Re: 7.3.2 vs 7.1.2  (Victor Yegorov <viktors.jegorovs@nordlb.lv>)
Responses Re: 7.3.2 vs 7.1.2
List pgsql-performance
On Tue, May 20, 2003 at 05:07:13PM +0300, Victor Yegorov wrote:
>
> As you can see, in 7.2.1 index scan on loads (load_rcn_id_idx) takes 0.04..786.13,
> but in 7.3.2 - 0.07..4486.76.
>
> Also, note the difference in the:
>
> 7.2.1 "... rows=147281 width=4) ..."
> 7.3.2 "... rows=147281 width=181) ..."
>
> My guesses:
>
> 1. Check your index.
> 2. Do vacuum analyze again.
> 3. This part:
> (loads l JOIN (SELECT rcn_details.id, rcn_details.date_pour FROM rcn_details) r ON ((r.id = l.rcn_id)))
>

I've tried to simplify it, nothing happens -- the same effect !
The question is -- why it scans my indexes so long ?
I've created "clean" experiment: the same machine, the same dump.
And perform the same procedure for each DB (btw, now it's 7.2.4 vs 7.3.1 :-)):

1. Install DB.
2. Init DB.
3. Fix postgresql.conf
4. Load dump.
5. vacuum analyze.
6. query !

Difference is the same like 5 seconds vs 50 seconds...

--
Eugene Fokin
SOLVO Ltd. Company

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