From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Brook <paul@codesourcery.com>
Subject: Re: [Qemu-devel] [RFC][PATCH] Add HPET emulation to qemu (v2)
Date: Sat, 2 Aug 2008 12:42:29 +0100
Message-ID: <200808021242.30784.paul@codesourcery.com>
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Cc: Beth Kon <eak@us.ibm.com>, Alexander Graf <agraf@suse.de>,
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> I've been playing with CONFIG_NO_HZ and been surprised by the
> results.  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). Ultimately
> this depends on exactly what the guest is doing

Linux can use the existing acpi PM timer a NO_HZ clocksource.

Paul