Re: PG writes a lot to the disk - Mailing list pgsql-performance

From Laurent Raufaste
Subject Re: PG writes a lot to the disk
Date
Msg-id 669dc9710803200348x64122249jd2ac5924d78a6da0@mail.gmail.com
Whole thread Raw
In response to PG writes a lot to the disk  ("Laurent Raufaste" <analogue@glop.org>)
Responses Re: PG writes a lot to the disk  ("Albe Laurenz" <laurenz.albe@wien.gv.at>)
List pgsql-performance
2008/3/19, Laurent Raufaste <analogue@glop.org>:
>  What does it writes so much in the base directory ? If it's some
>  temporary table or anything, how can I locate it so I can fix the
>  problem ?

Thanks for your help everybody ! I fixed the problem by doing an
ANALYZE to every table (yes I'm so noob ;) ).

The problem was that the optimiser didn't know how to run the queries
well and used millions of tuples for simple queries. For each tuple
used it was updating some bit in the table file, resulting in a huge
writing activity to that file.

After the ANALYZE, the optimiser worked smarter, used thousand time
less tuple for each query, and PG was not required to update so much
bits in the table files.

The server is now OK, thanks !

--
Laurent Raufaste
<http://www.glop.org/>

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