Re: Linux I/O tuning: CFQ vs. deadline - Mailing list pgsql-performance

From david@lang.hm
Subject Re: Linux I/O tuning: CFQ vs. deadline
Date
Msg-id alpine.DEB.2.00.1002101749150.4721@asgard.lang.hm
Whole thread Raw
In response to Re: Linux I/O tuning: CFQ vs. deadline  (Greg Smith <greg@2ndquadrant.com>)
Responses Re: Linux I/O tuning: CFQ vs. deadline  (Greg Smith <greg@2ndquadrant.com>)
List pgsql-performance
On Wed, 10 Feb 2010, Greg Smith wrote:

> Scott Marlowe wrote:
>> I'd love to see someone do a comparison of early to mid 2.6 kernels (2.6.18
>> like RHEL5) to very
>> up to date 2.6 kernels.  On fast hardware.
>
> I'd be happy just to find fast hardware that works on every kernel from the
> RHEL5 2.6.18 up to the latest one without issues.

it depends on your definition of 'fast hardware'

I have boxes that were very fast at the time that work on all these
kernels, but they wouldn't be considered fast by todays's standards.

remember that there is a point release about every 3 months, 2.6.33 is
about to be released, so this is a 3 x (33-18) = ~45 month old kernel.

hardware progresses a LOT on 4 years.

most of my new hardware has no problems with the old kernels as well, but
once in a while I run into something that doesn't work.

David Lang

pgsql-performance by date:

Previous
From: Greg Smith
Date:
Subject: Re: Linux I/O tuning: CFQ vs. deadline
Next
From: Bryce Nesbitt
Date:
Subject: Re: Re: 512,600ms query becomes 7500ms... but why? Postgres 8.3 query planner quirk?