From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Subject: Re: [patch 3/3] KVM: PIT: fix injection logic and count
Date: Tue, 29 Jul 2008 11:42:57 -0300
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Cc: Sheng Yang <sheng.yang@intel.com>, kvm <kvm@vger.kernel.org>
To: Avi Kivity <avi@qumranet.com>
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On Tue, Jul 29, 2008 at 03:55:26PM +0300, Avi Kivity wrote:
> Sometimes the guest leaves the timer enabled but the output pin masked,  
> (e.g. it doesn't use the timer bug doesn't bother to turn it off  
> properly).  This results in extraneous interrupts, causing unnecessary  
> vmexits and increased power usage.
>
> But if we detect that the guest isn't processing the interrupts, we can  
> turn the timer off, and after the next injection, calculate the number  
> of missing interrupts, and turn the timer on again.  This will have to  
> be done carefully (taking care of the guest adjusting the frequency  
> during the period where we missed injections, for example).

Sounds like a good idea, I'll try something later.

>
> Comments?  Questions?  Patches?