From mboxrd@z Thu Jan 1 00:00:00 1970 From: xuehai zhang Subject: Re: open/stat64 syscalls run faster on Xen VM than standard Linux Date: Mon, 28 Nov 2005 09:28:31 -0600 Message-ID: <438B221F.6000202@cs.uchicago.edu> References: <907625E08839C4409CE5768403633E0B0EAAC4@sefsexmb1.amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <907625E08839C4409CE5768403633E0B0EAAC4@sefsexmb1.amd.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: "Petersson, Mats" Cc: Xen Mailing List List-Id: xen-devel@lists.xenproject.org Petersson, Mats wrote: >>-----Original Message----- >>From: xen-devel-bounces@lists.xensource.com >>[mailto:xen-devel-bounces@lists.xensource.com] On Behalf Of >>Anthony Liguori >>Sent: 28 November 2005 14:39 >>To: xuehai zhang >>Cc: Xen Mailing List >>Subject: Re: [Xen-devel] open/stat64 syscalls run faster on >>Xen VM than standard Linux >> >>This may just be the difference between having the extra >>level of block caching from using a loop back device. >> >>Try running the same benchmark on a domain that uses an >>actual partition. While the syscalls may appear to be >>faster, I imagine it's because the cost of pulling in a block >>has already been payed so the overall workload is unaffected. > > > And this would be the same as running standard linux with the loopback > file-system mounted and chroot to the local file-system, or would that > be different? [I'm asking because I don't actually understand enough > about how it works to know what difference it makes, and I would like to > know, because at some point I'll probably need to know this.] Mats, I will do this experiments and see what is happening (as I promised in the popen threads). Thanks. Xuehai