From: Dirk Lutzebäck <lutzeb@aeccom.com>
To: J. Andrew Rogers <jrogers@neopolitan.com>
Cc: josh@agliodbs.com, pgsql-performance@postgresql.org, Sven Geisler <sgeisler@aeccom.com>
Subject: Re: Performance problems on 4/8way Opteron (dualcore) HP
Date: Sun, 31 Jul 2005 12:12:32 +0200
Message-ID: <42ECA410.7020804@aeccom.com> (raw)
In-Reply-To: <BF0FCFE1.71F%jrogers@neopolitan.com>
References: <BF0FCFE1.71F%jrogers@neopolitan.com>
Anybody knows if RedHat is already supporting this patch on an
enterprise version?
Regards,
Dirk
J. Andrew Rogers wrote:
> On 7/29/05 10:46 AM, "Josh Berkus" <josh@agliodbs.com> wrote:
>
>>>does anybody have expierence with this machine (4x 875 dual core Opteron
>>>CPUs)?
>>
>>Nope. I suspect that you may be the first person to report in on
>>dual-cores. There may be special compile issues with dual-cores that
>>we've not yet encountered.
>
>
>
> There was recently a discussion of similar types of problems on a couple of
> the supercomputing lists, regarding surprisingly substandard performance
> from large dual-core opteron installations.
>
> The problem as I remember it boiled down to the Linux kernel handling
> memory/process management very badly on large dual core systems --
> pathological NUMA behavior. However, this problem has apparently been fixed
> in Linux v2.6.12+, and using the more recent kernel on large dual core
> systems generated *massive* performance improvements on these systems for
> the individuals with this issue. Using the patched kernel, one gets the
> performance most people were expecting.
>
> The v2.6.12+ kernels are a bit new, but they contain a very important
> performance patch for systems like the one above. It would definitely be
> worth testing if possible.
>
>
> J. Andrew Rogers
>
>
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: lutzeb@aeccom.com, jrogers@neopolitan.com, sgeisler@aeccom.com
Subject: Re: Performance problems on 4/8way Opteron (dualcore) HP
In-Reply-To: <42ECA410.7020804@aeccom.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox