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

From Jeff
Subject Re: Linux I/O tuning: CFQ vs. deadline
Date
Msg-id 39DDB34B-C375-46ED-83D2-688A32188100@torgo.978.org
Whole thread Raw
In response to Re: Linux I/O tuning: CFQ vs. deadline  (david@lang.hm)
Responses Re: Linux I/O tuning: CFQ vs. deadline  (Greg Smith <greg@2ndquadrant.com>)
List pgsql-performance
On Feb 8, 2010, at 11:35 PM, david@lang.hm wrote:
>
>> And, yes, the whole I/O scheduling approach in Linux was just
>> completely redesigned for a very recent kernel update.  So even
>> what we think we know is already obsolete in some respects.
>>

I'd done some testing a while ago on the schedulers and at the time
deadline or noop smashed cfq.  Now, it is 100% possible since then
that they've made vast improvements to cfq and or the VM to get better
or similar performance.  I recall a vintage of 2.6 where they severely
messed up the VM. Glad I didn't upgrade to that one :)

Here's the old post: http://archives.postgresql.org/pgsql-performance/2008-04/msg00155.php


--
Jeff Trout <jeff@jefftrout.com>
http://www.stuarthamm.net/
http://www.dellsmartexitin.com/




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