From: Simon Riggs <simon@2ndQuadrant.com>
To: Hannu Krosing <hannu@2ndQuadrant.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: VACUUMs and WAL
Date: Tue, 28 Oct 2008 10:10:45 +0000
Message-ID: <1225188645.3971.118.camel@ebony.2ndQuadrant> (raw)
In-Reply-To: <1225187130.7721.5.camel@huvostro>
References: <1225183785.3971.114.camel@ebony.2ndQuadrant>
<1225187130.7721.5.camel@huvostro>
On Tue, 2008-10-28 at 11:45 +0200, Hannu Krosing wrote:
> On Tue, 2008-10-28 at 08:49 +0000, Simon Riggs wrote:
> > Looking at a VACUUM's WAL records makes me think twice about the way we
> > issue a VACUUM.
> >
> > 1. First we scan the heap, issuing a HEAP2 clean record for every block
> > that needs cleaning.
>
> IIRC the first heap pass just collects info and does nothing else.
> Is this just an empty/do-nothing WAL record ?
8.3 changed that; it used to work that way. I guess I never looked at
the amount of WAL being generated.
--
Simon Riggs www.2ndQuadrant.com
PostgreSQL Training, Services and Support
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To: pgsql-hackers@postgresql.org
Cc: simon@2ndQuadrant.com, hannu@2ndQuadrant.com
Subject: Re: VACUUMs and WAL
In-Reply-To: <1225188645.3971.118.camel@ebony.2ndQuadrant>
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