Subject: Re: 8.2 Autovacuum BUG ?
From: Mark Lewis <mark.lewis@mir3.com>
To: Pallav Kalva <pkalva@livedatagroup.com>
Cc: Alvaro Herrera <alvherre@commandprompt.com>, Tom Lane <tgl@sss.pgh.pa.us>,
	pgsql-performance@postgresql.org
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	<25038.1188574775@sss.pgh.pa.us> <46D83C50.3040409@livedatagroup.com>
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Organization: MIR3, Inc.
Date: Fri, 31 Aug 2007 09:29:31 -0700
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On Fri, 2007-08-31 at 12:25 -0400, Pallav Kalva wrote:
> Can you please correct me if I am wrong, I want to understand how this 
> works.
> Based on what you said, it will run autovacuum again when it passes 200M 
> transactions, as SELECTS are transactions too and are going on these 
> tables.
> But the next time when it runs autovacuum, it shouldnt freeze the tuples 
> again as they are already frozen and wont generate lot of archive logs ?
> Or is this because of it ran autovacuum for the first time on this db ? 
> just the first time it does this process ?

That is correct.  The tuples are now frozen, which means that they will
not need to be frozen ever again unless you insert/update any records.