Message-ID: <43A127D3.1070106@cosmosbay.com>
Date: Thu, 15 Dec 2005 09:22:43 +0100
From: Eric Dumazet <dada1@cosmosbay.com>
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To: Ravikiran G Thirumalai <kiran@scalex86.org>
Cc: Andi Kleen <ak@suse.de>, linux-kernel@vger.kernel.org, discuss@x86-64.org,
       Andrew Morton <akpm@osdl.org>, dada1@cosmobay.com
Subject: Re: [patch 3/3] x86_64: Node local pda take 2 -- node local pda allocation
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Ravikiran G Thirumalai a ?crit :
> Patch uses a static PDA array early at boot and reallocates processor PDA
> with node local memory when kmalloc is ready, just before pda_init.
> The boot_cpu_pda is needed since the cpu_pda is used even before pda_init for
> that cpu is called.   
> (pda_init is called when APs are brought on at rest_init().  But
> setup_per_cpu_areas is called early in start_kernel and 
> sched_init uses the per-cpu offset table early)

That seems good, thank you !

Do you have an idea of the performance gain we could expect from this node 
local pda allocation ?

Say a CPU is on Node 1,  was a change in pda (allocated on Node 0) immediatly 
mirrored on remote node or not ?

Eric
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