From: Shaun Thomas <sthomas@peak6.com>
To: Greg Spiegelberg <gspiegelberg@gmail.com>
Cc: Reuven M. Lerner <reuven@lerner.co.il>
Cc: Andrew Dunstan <andrew@dunslane.net>
Cc: Marcin Mańk <marcin.mank@gmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Very long deletion time on a 200 GB database
Date: Thu, 23 Feb 2012 12:05:01 -0600
Message-ID: <4F467FCD.8090100@peak6.com> (raw)
In-Reply-To: <CAEtnbpUZkdg-gH_AcbTMG41yN+Y0ECXdtnGTdf232B6T3v_1SA@mail.gmail.com>
References: <4F45FB55.1020600@lerner.co.il>
<CAK61fk6bSQtmDUzm2rNv33kN4Oar_dYZ-yFEa9zR_zLL8L9esQ@mail.gmail.com>
<4F464C49.4050503@dunslane.net>
<4F465A7A.4000905@lerner.co.il>
<CAEtnbpUZkdg-gH_AcbTMG41yN+Y0ECXdtnGTdf232B6T3v_1SA@mail.gmail.com>
On 02/23/2012 11:56 AM, Greg Spiegelberg wrote:
> I know there are perils in using ctid but with the LOCK it should be
> safe. This transaction took perhaps 30 minutes and removed 100k rows
> and once the table was VACUUM'd afterward it freed up close to 20 GB
> on the file system.
It took *30 minutes* to delete 100k rows? And 100k rows were using 20GB?
Is that off by an order of magnitude?
Using the ctid is a cute trick, though. :)
--
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 500 | Chicago IL, 60604
312-444-8534
sthomas@peak6.com
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To: pgsql-performance@postgresql.org
Cc: sthomas@peak6.com, gspiegelberg@gmail.com, reuven@lerner.co.il, andrew@dunslane.net, marcin.mank@gmail.com
Subject: Re: Very long deletion time on a 200 GB database
In-Reply-To: <4F467FCD.8090100@peak6.com>
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