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Subject: Re: CLOG Patch
From: "Simon Riggs" <simon@2ndquadrant.com>
To: "Jignesh K. Shah" <J.K.Shah@Sun.COM>
Cc: "Tom Lane" <tgl@sss.pgh.pa.us>, "Josh Berkus" <josh@agliodbs.com>,
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On Fri, 2007-08-03 at 16:09 -0400, Jignesh K. Shah wrote:

> This patch seems to work well (both with 32 and 64 value but not with 16 
> and the default 8). 

Could you test at 24 please also? Tom has pointed out the additional
cost of setting this higher, even in workloads that don't benefit from
the I/O-induced contention reduction.

> Is there a way we can integrate this in 8.3?

I just replied to Josh's thread on -hackers about this.

> This will improve out of box performance quite a bit for high number of 
> users (atleat 30% in my OLTP test)

Yes, thats good. Will this have a dramatic effect on a particular
benchmark, or for what reason might we need this? Tom has questioned the
use case here, so I think it would be good to explain a little more for
everyone. Thanks.

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