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Date: Tue, 23 Jan 2007 09:48:46 +0100
From: Martijn van Oosterhout <kleptog@svana.org>
To: Pavan Deolasee <pavan.deolasee@gmail.com>
Cc: pgsql-hackers@postgresql.org
Subject: Re: Free space management within heap page
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On Tue, Jan 23, 2007 at 01:48:08PM +0530, Pavan Deolasee wrote:
> I am thinking that maintaining fragmented free space within a heap page
> might be a good idea. It would help us to reuse the free space ASAP witho=
ut
> waiting for a vacuum run on the page. This in turn will lead to lesser he=
ap
> bloats and also increase the probability of placing updated tuple in the
> same heap page as the original one.

<snip>

Nice idea but:

> We might not be able to reuse the line pointers because indexes may have
> references to it. All such line pointers will be freed when the page is
> vacuumed during the regular vacuum.

The overwhelming vast majoirty of tuples are going to be in one or more
indexes. Which means nearly all tuples are going to fall into this
category. So where's the benefit?

Have a nice day,
--=20
Martijn van Oosterhout   <kleptog@svana.org>   http://svana.org/kleptog/
> From each according to his ability. To each according to his ability to l=
itigate.

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