Re: How is random_page_cost=4 ok?

From: "Nikolas Everett" <nik9000(at)gmail(dot)com>
To: "Gregory Stark" <stark(at)enterprisedb(dot)com>
Cc: "Josh Berkus" <josh(at)agliodbs(dot)com>, "Greg Smith" <gsmith(at)gregsmith(dot)com>, Postgres <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: How is random_page_cost=4 ok?
Date: 2008-10-11 00:41:07
Message-ID: d4e11e980810101741rccb1e99v10ebe5d1d9d1ed3b@mail.gmail.com
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>
> In any case your experience doesn't match mine. On a machine with a sizable
> raid controller setting random_page_cost higher does generate, as expected,
> plans with more bitmap heap scans which are in fact faster.
>

We're running postgres backed by a NetApp 3020 via fiber and have had a lot
of success setting random page cost very high (10). Sequential reads are
just that much faster. I'm not sure if thats because we've configured
something wrong or what, but thats a really useful knob for us.

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