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	<4BA0AAD1.5040508@2ndquadrant.com> <27969.1268836243@sss.pgh.pa.us>
From: Rob Wultsch <wultsch@gmail.com>
Date: Wed, 17 Mar 2010 08:07:16 -0700
Message-ID: <2c5ef4e31003170807x3f26dd77v57a1631094bc5270@mail.gmail.com>
Subject: Re: Building multiple indexes concurrently
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Greg Smith <greg@2ndquadrant.com>, pgsql-performance@postgresql.org
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On Wed, Mar 17, 2010 at 7:30 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Greg Smith <greg@2ndquadrant.com> writes:
>> Rob Wultsch wrote:
>>> At a minimum I assume that if both of the commands were started at
>>> about the same time they would each scan the table in the same
>>> direction and whichever creation was slower would benefit from most of
>>> the table data it needed being prepopulated in shared buffers. Is this
>>> the case?
>
>> This might be optimistic;
>
> No, it's not optimistic in the least, at least not since we implemented
> synchronized seqscans (in 8.3 or thereabouts).
>
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0regards, tom lane
>

Where can I find details about this in the documentation?

--=20
Rob Wultsch
wultsch@gmail.com