Re: Upgrading from 9.2 to 9.3 causes performance degradation

Jeff: I ran a VACUUM FULL ANALYZE and retested. No significative change was notices, the explain is availiable in

9.3 - After VACUUM FULL ANALYZE - http://explain.depesz.com/s/rVoW
9.3 - Original - http://explain.depesz.com/s/Vwt

Adrian: I'll try to send the query attached. My doubts are: why 9.3 is slower then 9.2 with the same database/configuration/harware/query? Even worst, why 9.3 got slower results on a better HW, where 9.2 improved on the same scenario.

I've just ran the explains on my new server, links below:
9.2 - http://explain.depesz.com/s/AeD
9.3 - http://explain.depesz.com/s/1sp

For comparison sake, old server:
9.2 - http://explain.depesz.com/s/bXIo
9.3 - http://explain.depesz.com/s/Vwt

I really appreciate your help.

Thanks again,

--
Álvaro Nunes Melo Atua Sistemas de Informação
alvaro(at)atua(dot)com(dot)br http://www.atua.com.br
(54) 9976-0106 (54) 3045-4144

----- Mensagem original -----

De: "Jeff Janes" <jeff(dot)janes(at)gmail(dot)com>
Para: "Álvaro Nunes Lemos Melo" <al_nunes(at)atua(dot)com(dot)br>
Cc: pgsql-general(at)postgresql(dot)org
Enviadas: Segunda-feira, 24 de março de 2014 15:29:38
Assunto: Re: [GENERAL] Upgrading from 9.2 to 9.3 causes performance degradation

On Mon, Mar 24, 2014 at 7:45 AM, Álvaro Nunes Lemos Melo < al_nunes(at)atua(dot)com(dot)br > wrote:

==> Venkata
> After the migration to hardware and to the new version 9.3, any changes have been done in the postgresql.conf compared to the old settings ?
No, as I wrote initially, I'd double checked and the four conf files have the same parameters.

> Any maintenance activities (VACUUM or VACUUM FULL and ANALYZE) have been performed after the migration ?
ANALYZE yes. VACUUM or VACUUM FULL no, because I ran the test on recently restores and unchanged databases.

How did you do the restore? Please VACUUM and retest. At best it will fix the problem, and if it doesn't it will at least rule out a bunch of possibilities for the source of the problem.

Cheers,

Jeff