Date: Mon, 07 Nov 2005 17:34:37 -0800
From: "Martin J. Bligh" <mbligh@mbligh.org>
Reply-To: "Martin J. Bligh" <mbligh@mbligh.org>
To: Anton Blanchard <anton@samba.org>, Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Brian Twichell <tbrian@us.ibm.com>,
       David Lang <david.lang@digitalinsight.com>,
       linux-kernel@vger.kernel.org, slpratt@us.ibm.com
Subject: Re: Database regression due to scheduler changes ?
Message-ID: <105220000.1131413677@flay>
In-Reply-To: <20051108011547.GP12353@krispykreme>
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>> I would also take a look at removing SD_WAKE_IDLE from the flags.
>> This flag should make balancing more aggressive, but it can have
>> problems when applied to a NUMA domain due to too much task
>> movement.
> 
> I was wondering how ppc64 ended up with different parameters in the NODE
> definitions (added SD_BALANCE_NEWIDLE and SD_WAKE_IDLE)	and it looks
> like it was Andrew :)
> 
> http://lkml.org/lkml/2004/11/2/205
> 
> It looks like balancing was not agressive enough on his workload too.
> Im a bit uneasy with only ppc64 having the two flags though.
> 
> Im also considering adding balance on fork for ppc64, it seems like a
> lot of people like to run stream like benchmarks and Im getting tired of
> telling them to lock their threads down to cpus.

Please don't screw up everything else just for stream. It's a silly 
frigging benchmark. There's very little real-world stuff that really
needs balance on fork, as opposed to balance on clone, and it'll slow
down everything else.

M.


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