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From: Jeff Janes <jeff.janes@gmail.com>
To: Jesper Krogh <jesper@krogh.cc>
Cc: pgsql-performance@postgresql.org
Subject: Re: reducing random_page_cost from 4 to 2 to force index scan
Date: Mon, 16 May 2011 09:45:28 -0700
Message-ID: <BANLkTimw2xWYQ_Hz4vtLXx-2nZRjRfoMMw@mail.gmail.com> (raw)
In-Reply-To: <4DD0ACD0.1090801@krogh.cc>
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On Sun, May 15, 2011 at 9:49 PM, Jesper Krogh <jesper@krogh.cc> wrote:
>
> Ok, it may not work as well with index'es, since having 1% in cache may very
> well mean that 90% of all requested blocks are there.. for tables in should
> be more trivial.

Why would the index have a meaningful hot-spot unless the underlying
table had one as well?  (Of course the root block will be a hot-spot,
but certainly not 90% of all requests)

Cheers,

Jeff



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