Re: Table and Index compression

From: Josh Berkus <josh(at)agliodbs(dot)com>
To: Pierre Frédéric Caillaud <lists(at)peufeu(dot)com>
Cc: Greg Stark <gsstark(at)mit(dot)edu>, Sam Mason <sam(at)samason(dot)me(dot)uk>, pgsql-hackers(at)postgresql(dot)org
Subject: Re: Table and Index compression
Date: 2009-08-07 17:28:49
Message-ID: 4A7C6451.9000707@agliodbs.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Pierre,

> I added a field in PageHeader which contains :
> - 0 to indicate a non-compressed page
> - length of compressed data if compressed
>
> If compression gains nothing (ie gains less than 4K), the page is
> stored raw.
>
> It seems that only pages having a PageHeader are handled by md.c, so
> it should work (am I mistaken ?)

Well, there's the issue of upgradability; this would require us to have
an incompatible upgrade of on-disk formats. So we don't want to go
further down this route unless we're sure it's worthwhile.

--
Josh Berkus
PostgreSQL Experts Inc.
www.pgexperts.com

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Todd A. Cook 2009-08-07 17:29:56 Re: slow commits with heavy temp table usage in 8.4.0
Previous Message Tom Lane 2009-08-07 16:50:39 Re: Fixing geometic calculation