From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anthony Liguori Subject: Re: [PATCH 0/6] In kernel PIT patch Date: Thu, 06 Mar 2008 14:56:34 -0600 Message-ID: <47D05A82.304@codemonkey.ws> References: <200803041822.40285.sheng.yang@intel.com> <47CD7038.6000200@codemonkey.ws> <1204672734.25172.24.camel@localhost.localdomain> <47CDEE50.3060206@codemonkey.ws> <1204712042.31109.23.camel@localhost.localdomain> <47CEB519.6080305@codemonkey.ws> <47CED8AD.80201@qumranet.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: kvm-devel@lists.sourceforge.net To: Avi Kivity Return-path: In-Reply-To: <47CED8AD.80201@qumranet.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: kvm-devel-bounces@lists.sourceforge.net Errors-To: kvm-devel-bounces@lists.sourceforge.net List-Id: kvm.vger.kernel.org Avi Kivity wrote: > >> The thing I'm trying to get at is a quantitative statement about why >> moving the pit into the kernel is the right thing. I'll try to give >> the patches a try myself in the next couple of days. I don't think >> it's obvious that it's the right thing to do without some sort of >> benchmark supporting it. >> > > Playing a movie is better than any benchmark; it reflects actual user > experience in a real and important use case. Benchmarks are > substitutes for real use cases, not the goal of the optimization. I tried out WinXP with the standard HAL and the in-kernel APIC patches. I did not see any appreciable improvement in multimedia playback (video or audio). I still get the same amount of jitters. I've tried with and without -tdf too. So far, the smoothest play back I've gotten is using the ACPI HAL. Can you point to a particular example where you see an improvement? Perhaps a divx or movie trailer that is better with it than without it? Regards, Anthony Liguori ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/