Message-ID: <54D3CF2C.6030203@redhat.com>
Date: Thu, 05 Feb 2015 21:14:36 +0100
From: Paolo Bonzini <pbonzini@redhat.com>
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To: Rik van Riel <riel@redhat.com>, Jan Kiszka <jan.kiszka@siemens.com>,
        linux-kernel@vger.kernel.org, kvm@vger.kernel.org
CC: rkrcmar@redhat.com, mtosatti@redhat.com
Subject: Re: [PATCH RFC] kvm: x86: add halt_poll module parameter
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On 05/02/2015 20:23, Rik van Riel wrote:
>> > 3) long term anyway we want it to auto tune, which is better than tuning
>> > it per-VM.
> We may want to auto tune it per VM.

We may even want to auto tune it per VCPU.

> However, if we make auto tuning work well, I do not
> think we want to expose a user visible tunable per
> VM, and commit to keeping that kind of interface
> around forever.

Exactly.  We probably want module parameters to tune the minimum/maximum
values (which includes the special cases of disabling polling
altogether, and disabling the autotuning while leaving polling enabled),
but committing to a per-VM interface is premature.

Paolo
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