Date: Tue, 31 Mar 2009 19:35:53 -0400 (EDT)
From: Greg Smith <gsmith@gregsmith.com>
To: Kevin Grittner <Kevin.Grittner@wicourts.gov>
cc: pgsql-performance@postgresql.org
Subject: Re: Strange behavior: pgbench and new Linux kernels
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On Tue, 31 Mar 2009, Kevin Grittner wrote:

>>>> On Thu, Apr 17, 2008 at  7:26 PM, Greg Smith wrote:
>
>> On this benchmark 2.6.25 is the worst kernel yet:
>
>> It seems I have a lot of work ahead of me here
>> to nail down and report what's going on here.
>
> I don't remember seeing a follow-up on this issue from last year.
> Are there still any particular kernels to avoid based on this?

I never got any confirmation that the patches that came out of my 
discussions with the kernel developers were ever merged.  I'm in the 
middle of a bunch of pgbench tests this week, and one of the things I 
planned to try was seeing if the behavior has changed in 2.6.28 or 2.6.29. 
I'm speaking about pgbench at the PostgreSQL East conference this weekend 
and will have an update by then (along with a new toolchain for automating 
large quantities of pgbench tests).

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD