Re: Small FSM is too large

From: Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>
To: Simon Riggs <simon(at)2ndQuadrant(dot)com>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: Small FSM is too large
Date: 2010-06-20 17:39:31
Message-ID: 4C1E5253.2060608@enterprisedb.com
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On 20/06/10 13:56, Simon Riggs wrote:
> I notice that if I vacuum a 1 row table I get a FSM that is 24576 bytes
> in size, or 3 database blocks.
>
> Why is it not 1 block, or better still 0 blocks for such a small table?

It was just less code to write and test that way. The FSM tree is always
constant height, three levels, to keep things simple.

--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com

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