Re: [PATCHES] Full page writes improvement, code update

Simon Riggs <simon@2ndquadrant.com>

From: "Simon Riggs" <simon@2ndquadrant.com>
To: <josh@agliodbs.com>
Cc: <pgsql-hackers@postgresql.org>, "Koichi Suzuki" <suzuki.koichi@oss.ntt.co.jp>, <pgsql-patches@postgresql.org>
Date: 2007-03-29T20:28:36Z
Lists: pgsql-hackers
On Thu, 2007-03-29 at 11:45 -0700, Josh Berkus wrote:

> > OK, different question:
> > Why would anyone ever set full_page_compress = off?
> 
> The only reason I can see is if compression costs us CPU but gains RAM & 
> I/O.  I can think of a lot of applications ... benchmarks included ... 
> which are CPU-bound but not RAM or I/O bound.  For those applications, 
> compression is a bad tradeoff.
> 
> If, however, CPU used for compression is made up elsewhere through smaller 
> file processing, then I'd agree that we don't need a switch.

Koichi-san has explained things for me now.

I misunderstood what the parameter did and reading your post, ISTM you
have as well. I do hope Koichi-san will alter the name to allow
everybody to understand what it does.

-- 
  Simon Riggs             
  EnterpriseDB   http://www.enterprisedb.com