From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <anthony@codemonkey.ws>
Subject: Re: [Qemu-devel] [RFC][PATCH] Add HPET emulation to qemu (v2)
Date: Sat, 02 Aug 2008 09:46:30 -0500
Message-ID: <48947346.5080605@codemonkey.ws>
References: <1217675114-17670-1-git-send-email-eak@us.ibm.com> <20080802113812.GD4535@implementation>
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To: Samuel Thibault <samuel.thibault@ens-lyon.org>,
	qemu-devel@nongnu.org, Beth Kon <eak@us.ibm.com>,
	Alexander Graf <agraf@suse.de>, kvm@vger.kernel.org
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Samuel Thibault wrote:
> Beth Kon, le Sat 02 Aug 2008 06:05:14 -0500, a =E9crit :
>  =20
>> I was trying to reproduce the wakeup every 10ms that=20
>> Samuel Thibault mentioned, thinking the HPET would improve it.=20
>> But for an idle guest in both cases (with and without HPET), the=20
>> number of wakeups per second was relatively low (28).
>>    =20
>
> I was referring to vl.c's timeout =3D 10; which makes the select call
> use a timeout of 10ms. That said, "/* If all cpus are halted then wai=
t
> until the next IRQ */", so maybe that's why you get slower wakeups pe=
r
> second.  I'm still surprised because of the call to qemu_mod_timer in
> pit_irq_timer_update which should setup at least a 100Hz timer with
> linux guests (when they don't have HPET available).
>  =20

The patch disables that when hpet is active.

Regards,

Anthony Liguori

> Samuel
>
>
>  =20