From: Guillaume Cottenceau <gc@mnc.ch>
To: pasman pasmański <pasman.p@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Query uses incorrect index
Date: Wed, 22 Dec 2010 10:38:15 +0100
Message-ID: <874oa6w3js.fsf@meuh.mnc.lan> (raw)
In-Reply-To: <AANLkTin5Mrjm48BYXuzLn_atpVN40KvhqjumH15QDLmu@mail.gmail.com>
References: <AANLkTin5Mrjm48BYXuzLn_atpVN40KvhqjumH15QDLmu@mail.gmail.com>
pasman pasmański <pasman.p 'at' gmail.com> writes:
> Thanks for reply.
> I tested random changes and query runs fastest after:
>
> set seq_page_cost = 0.1;
> set random_page_cost = 0.1;
> cpu_operator_cost = 0.01
If I'm correct, you're basically telling postgresql that your
disk is unusually fast compared to your CPU. Even if some queries
will run faster from a side-effect of these settings, you're
likely to create other random problems...
--
Guillaume Cottenceau
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To: pgsql-performance@postgresql.org
Cc: gc@mnc.ch, pasman.p@gmail.com
Subject: Re: Query uses incorrect index
In-Reply-To: <874oa6w3js.fsf@meuh.mnc.lan>
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