From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamie Lokier Subject: Re: [Qemu-devel] [PATCH 1/2] Add HPET emulation to qemu (v3) Date: Fri, 17 Oct 2008 16:49:32 +0100 Message-ID: <20081017154932.GA14229@shareable.org> References: <1224245854.3399.7.camel@beth-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Alexander Graf , kvm@vger.kernel.org To: qemu-devel@nongnu.org Return-path: Received: from mail2.shareable.org ([80.68.89.115]:48474 "EHLO mail2.shareable.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753873AbYJQPtk (ORCPT ); Fri, 17 Oct 2008 11:49:40 -0400 Content-Disposition: inline In-Reply-To: <1224245854.3399.7.camel@beth-laptop> Sender: kvm-owner@vger.kernel.org List-ID: Beth Kon wrote: > Clock drift on Linux is in the range of .017% - .019%, loaded and unloaded. I > haven't found a straightforward way to test on Windows and would appreciate > any pointers to existing approaches. Is there any reason why there should be any clock drift, when the guest is using a non-PIT clock? I'm probably being naive, but with 32-bit or 64-bit HPET counters available to the guest, and accurate values from the CMOS clock emulation, I don't see why drift would accumulate over the long term relative to the host clock. -- Jamie