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Date: Sat, 2 Aug 2008 12:38:12 +0100
From: Samuel Thibault <samuel.thibault@ens-lyon.org>
Subject: Re: [Qemu-devel] [RFC][PATCH] Add HPET emulation to qemu (v2)
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To: qemu-devel@nongnu.org
Cc: Beth Kon <eak@us.ibm.com>, Alexander Graf <agraf@suse.de>, kvm@vger.kernel.org

Beth Kon, le Sat 02 Aug 2008 06:05:14 -0500, a écrit :
> I was trying to reproduce the wakeup every 10ms that 
> Samuel Thibault mentioned, thinking the HPET would improve it. 
> But for an idle guest in both cases (with and without HPET), the 
> number of wakeups per second was relatively low (28).

I was referring to vl.c's timeout = 10; which makes the select call
use a timeout of 10ms. That said, "/* If all cpus are halted then wait
until the next IRQ */", so maybe that's why you get slower wakeups per
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).

Samuel