Re: 7.3.1 takes long time to vacuum table? - Mailing list pgsql-general

From Tom Lane
Subject Re: 7.3.1 takes long time to vacuum table?
Date
Msg-id 16814.1045712265@sss.pgh.pa.us
Whole thread Raw
In response to Re: 7.3.1 takes long time to vacuum table?  ("Mark Cave-Ayland" <m.cave-ayland@webbased.co.uk>)
Responses Re: 7.3.1 takes long time to vacuum table?  (Martijn van Oosterhout <kleptog@svana.org>)
List pgsql-general
Martijn van Oosterhout <kleptog@svana.org> writes:
> You could do the jump-back-in-blocks only if more than 30% of the table is
> empty and table is over 1GB. For the example here, a simple defragging
> algorithm would suffice; start at beginning and pack each tuple into the
> beginning of the file. It will move *every* tuple but it's more cache
> friendly. It's pretty extreme though.

And your evidence that it will actually be faster is ... ?

            regards, tom lane

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