Horton

Re: Buglist

Manfred Koizar <mkoi-pg@aon.at>

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From: Manfred Koizar <mkoi-pg@aon.at>
To: Shridhar Daithankar <shridhar_daithankar@persistent.co.in>
Cc: pgsql-general@postgresql.org, pgsql-hackers@postgresql.org
Date: 2003-08-22T14:09:44Z
Lists: pgsql-hackers, pgsql-general 
On Fri, 22 Aug 2003 16:27:53 +0530, Shridhar Daithankar
<shridhar_daithankar@persistent.co.in> wrote:
>What does FSM does then?

FSM = Free Space Map.  VACUUM writes information into the FSM, INSERTs
consult the FSM to find pages with free space for new tuples.

> I was under impression that FSM stores page 
>pointers and vacuum work on FSM information only. In that case, it wouldn't 
>have to waste time to find out which pages to clean.

This has been discussed yesterday here and on -hackers ("Decent VACUUM
(was: Buglist)").  We were talking about inventing a second data
structure: RSM.

Servus
 Manfred