Re: Pre-allocated free space for row - Mailing list pgsql-hackers

From Simon Riggs
Subject Re: Pre-allocated free space for row
Date
Msg-id 1125522424.3956.4.camel@localhost.localdomain
Whole thread Raw
In response to Re: Pre-allocated free space for row updating (like PCTFREE)  (Satoshi Nagayasu <nagayasus@nttdata.co.jp>)
List pgsql-hackers
On Wed, 2005-08-31 at 16:50 +0900, Satoshi Nagayasu wrote:
> Simon Riggs wrote:
> >>4. Allow to repair fragmentation in each page.
> >>
> >>Because updates cause fragmentation in the page.
> >>
> >>So we need to keep large continuous free space in each page,
> >>if we want to get more effective on PCTFREE feature.
> > 
> > 
> > ...doesn't VACUUM already do that?
> 
> VACUUM generates a huge load because it repaires all pages
> on the table file.
> 
> I think (more light-weight) repairing on a single page
> is needed to maintain free space in the specific page.

So PCTFREE is an OK idea, but lets drop #4, which is a separate idea and
not one that has gained agreeable consensus.

Best Regards, Simon Riggs



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