From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <anthony@codemonkey.ws>
Subject: Re: [PATCH 0/3] v2: KVM-userspace: add NUMA support for guests
Date: Tue, 09 Dec 2008 08:55:17 -0600
Message-ID: <493E86D5.5040602@codemonkey.ws>
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To: Avi Kivity <avi@redhat.com>
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Avi Kivity wrote:
> Andr=E9 Przywara wrote:
>>>> But I wouldn't load the admin with the burden of pinning, but let=20
>>>> this be done by QEMU/KVM. Maybe one could introduce a way to tell=20
>>>> QEMU/KVM to not pin the threads.
>>> This is where things start to get ugly...
>> Why? qemu-system-x86_64 -numa 2,pin:none and then use whatever metho=
d=20
>> you prefer (taskset, monitor) to pin the VCPUs (or left them unpinne=
d).
>
> I agree that for e.g. -numa 2, no host binding should occur.  Pinning=
=20
> memory or cpus to nodes should only occur if the user explicitly=20
> requested it.  Otherwise we run the risk of breaking load balancing.
>
> If the user chooses to pin, the responsibility is on them.  If not, w=
e=20
> should allow the host to do its thing.

Agreed.

Regards,

Anthony Liguori