From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: [RFC]degradation on IPF due to hypercall set irq
Date: Wed, 22 Nov 2006 09:26:20 +0000
Message-ID: <C189C83C.4DCA%keir@xensource.com>
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To: "Xu, Anthony" <anthony.xu@intel.com>
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On 22/11/06 09:24, "Xu, Anthony" <anthony.xu@intel.com> wrote:

>>>> To clarify, by event/main loop I mean: Flush just before qemu blocks
>>>> (otherwise multicall can be held for unbounded time, unless we set a
>>>> batching timeout which hopefully we can avoid needing to do).
> 
> Why otherwise multicall can be held for unbounded time?

Qemu only wakes up for device-model accesses. We don't know when the next of
those will be. So we should flush multicalls before the potentially blocking
select().

 -- Keir