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From: Daniel Lezcano <daniel.lezcano@linaro.org>
To: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Ingo Molnar <mingo@kernel.org>
Subject: [Question] : tie a task to a cluster when it shares memory resources
Date: Tue, 29 Oct 2013 10:32:33 -0700	[thread overview]
Message-ID: <526FF131.3070105@linaro.org> (raw)


Hi all,

I am not expert on the NUMA area and the scheduler but I was wondering 
the following:

On numa a process can define a memory policy to optimize access because 
remote memory access is suboptimal.

On a multicluster (aka multipackage), eg. Bi-Xeon 4 cores, the scheduler 
load balancing can spawn/balance a task to the second cluster even if 
the task is resulting from a fork or a pthread_create. If I am correct 
that could impact the performances due to L2 cache misses, no ?

Won't it be more efficient to tie a task to a cluster when it shares 
memory resources with another task on the same cluster ? and when the 
task does 'exec', this constraint is removed.

Thanks
-- Daniel

-- 
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                 reply	other threads:[~2013-10-29 17:32 UTC|newest]

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