From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Theurer Subject: Re: [PATCH] turn off writable page tables Date: Tue, 25 Jul 2006 21:25:14 -0500 Message-ID: <44C6D28A.3010004@us.ibm.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Ian Pratt Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Ian Pratt wrote: >> on Xeon MP processor, uniprocessor dom0 kernel, pae=y: >> >> benchmark c/s 10729 force_emulate >> ------------------------ --------- ------------- >> lmbench fork+exit: 469.5833 470.3913 usec, lower is better >> lmbench fork+execve: 1241.0000 1225.7778 usec, lower is better >> lmbench fork+/sbin/bash: 12190.000 12119.000 usec, lower is better >> > > It's kinda weird that these scores are so close -- I guess its just > coincidence that we must be getting something like an average of 10-20 > pte's updated per pagetable page and the cost of doing multiple emulates > perfectly balances the cost of unhooking/rehooking. > Ian, I'll try a small program which dirties a large chunk of memory. I'll also try the trace tool and see what we get. Thanks, Andrew