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Date: Tue, 17 Apr 2012 06:48:19 +0200
From: Michael Meskes <meskes@postgresql.org>
To: Boszormenyi Zoltan <zb@cybertec.at>
Cc: Noah Misch <noah@leadboat.com>, Michael Meskes <meskes@postgresql.org>,
	Robert Haas <robertmhaas@gmail.com>,
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	Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>,
	Bruce Momjian <bruce@momjian.us>
Subject: Re: ECPG FETCH readahead
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On Tue, Apr 17, 2012 at 06:02:34AM +0200, Boszormenyi Zoltan wrote:
> I listed two scenarios.
> 1. occasional bump of the readahead window for large requests,
>    for smaller requests it uses the originally set size
> 2. permanent bump of the readahead window for large requests
>    (larger than previously seen), all subsequent requests use
>    the new size
>=20
> Both can be implemented easily, which one do you prefer?
> If you always use very large requests, 1) behaves like 2)

I'd say let's go for #2. #1 is probably more efficient but not what the
programmer asked us to do. After all it's easy to increase the window siz=
e
accordingly if you want so as a programmer.

Michael
--=20
Michael Meskes
Michael at Fam-Meskes dot De, Michael at Meskes dot (De|Com|Net|Org)
Michael at BorussiaFan dot De, Meskes at (Debian|Postgresql) dot Org
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