Re: NUMA or not on dual Opteron

Andi Kleen
2005-01-13T20:26:57Z

Sander <sander@humilis.net> writes:

> Linus Torvalds wrote (ao):
>> On Wed, 12 Jan 2005, Sergey S. Kostyliov wrote:
>> > 2.6.10-rc1 hangs at boot stage for my dual opteron machine
>>
>> Oops, yes. There's some recent NUMA breakage - either disable
>> CONFIG_NUMA, or apply the patches that Andi Kleen just posted on the
>> mailing list (the second option much preferred, just to verify that
>> yes, that does fix it).
>
> I was under the impression that NUMA is useful on > 2-way systems only.
> Is this true, and if not, under what circumstances is NUMA useful on
> 2-way Opteron systems?

I don't know who gave you this impression, but it's wrong. Using a
NUMA aware kernel is an advantage under many workloads on a 2way
Opteron system.

>
> In other words: why should one want NUMA to be enabled or disabled for
> dual Opteron?

Because it is faster.

-Andi