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Date: Wed, 25 Sep 2002 13:57:22 -0700
From: "Martin J. Bligh" <mbligh@aracnet.com>
To: Andrew Theurer <habanero@us.ibm.com>, Andrew Morton <akpm@digeo.com>,
       William Lee Irwin III <wli@holomorphy.com>
cc: linux-kernel@vger.kernel.org
Subject: Re: 2.5.38-mm2 dbench $N times
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> Pretty sure each dbench child does it's own write/read to only it's own data.  
> There is no sharing that I am aware of between the processes.  

Right, but if the processes migrate easily, there's still no CPU locality.
Bill, do you want to try binding 1/32 of the processes to each CPU, and see if
that makes your throughput increase?

> How about running in tmpfs to avoid any disk IO at all?  

As far as I understand it, that won't help - we're operating out of pagecache anyway 
at this level, I think.
 
> Also, what's the policy for home node assignment on fork?  Are all of these 
> children getting the same home node assingnment??

Policy is random - the scheduler lacks any NUMA comprehension at the moment.
The numa sched mods would probably help a lot too.

M.