From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KqraC-0002Rl-SC for qemu-devel@nongnu.org; Fri, 17 Oct 2008 11:49:44 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KqraB-0002RJ-2a for qemu-devel@nongnu.org; Fri, 17 Oct 2008 11:49:44 -0400 Received: from [199.232.76.173] (port=60000 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KqraA-0002RE-Sr for qemu-devel@nongnu.org; Fri, 17 Oct 2008 11:49:42 -0400 Received: from mail2.shareable.org ([80.68.89.115]:40094) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1KqraA-0006YB-Js for qemu-devel@nongnu.org; Fri, 17 Oct 2008 11:49:42 -0400 Date: Fri, 17 Oct 2008 16:49:32 +0100 From: Jamie Lokier Subject: Re: [Qemu-devel] [PATCH 1/2] Add HPET emulation to qemu (v3) Message-ID: <20081017154932.GA14229@shareable.org> References: <1224245854.3399.7.camel@beth-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1224245854.3399.7.camel@beth-laptop> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Alexander Graf , kvm@vger.kernel.org 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