From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] irq: Add node_affinity CPU masks for smarter irqbalance
 hints
Date: Tue, 24 Nov 2009 19:26:15 +0100
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Cc: David Miller <davem@davemloft.net>,
	"peterz@infradead.org" <peterz@infradead.org>,
	"arjan@linux.intel.com" <arjan@linux.intel.com>,
	"yong.zhang0@gmail.com" <yong.zhang0@gmail.com>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"arjan@linux.jf.intel.com" <arjan@linux.jf.intel.com>,
	"netdev@vger.kernel.org" <netdev@vger.kernel.org>
To: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
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Peter P Waskiewicz Jr a =E9crit :
 That's the kind of thing PJ is trying to make available.
>=20
> Yes, that's exactly what I'm trying to do.  Even further, we want to
> allocate the ring SW struct itself and descriptor structures on other
> NUMA nodes, and make sure the interrupt lines up with those allocatio=
ns.
>=20

Say you allocate ring buffers on NUMA node of the CPU handling interrup=
t
on a particular queue.

If irqbalance or an admin changes /proc/irq/{number}/smp_affinities,
do you want to realloc ring buffer to another NUMA node ?

It seems complex to me, maybe optimal thing would be to use a NUMA poli=
cy to
spread vmalloc() allocations to all nodes to get a good bandwidth...