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Re: [PATCH] Allocate idle task for a CPU always on its local node

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On Tue, 17 May 2016, Andi Kleen wrote:
> From: Andi Kleen <ak@linux.intel.com>
> 
> Linux pre-allocates the task structs of the idle tasks for all possible CPUs.
> This currently means they all end up on node 0. This also implies
> that the cache line of MWAIT, which is around the flags field in the task
> struct, are all located in node 0.
> 
> We see a noticeable performance improvement on Knights Landing CPUs when
> the cache lines used for MWAIT are located in the local nodes of the CPUs
> using them. I would expect this to give a (likely slight) improvement
> on other systems too.
> 
> The patch implements placing the idle task in the node of
> its CPUs, by passing the right target node to copy_process()
> 
> Signed-off-by: Andi Kleen <ak@linux.intel.com>

Acked-by: Thomas Gleixner <tglx@linutronix.de>

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[PATCH] Allocate idle task for a CPU always on its local node Andi Kleen <andi@firstfloor.org> - 2016-05-17 23:00 +0200
  Re: [PATCH] Allocate idle task for a CPU always on its local node Andrew Morton <akpm@linux-foundation.org> - 2016-05-17 23:20 +0200
    Re: [PATCH] Allocate idle task for a CPU always on its local node Andi Kleen <ak@linux.intel.com> - 2016-05-18 00:00 +0200
  Re: [PATCH] Allocate idle task for a CPU always on its local node Thomas Gleixner <tglx@linutronix.de> - 2016-05-18 10:40 +0200

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