From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeremy Fitzhardinge Subject: Re: Re: Poor performance on HVM (kernbench) Date: Fri, 12 Sep 2008 07:20:05 -0700 Message-ID: <48CA7A95.3090605@goop.org> References: <1e16a9ed0809101123m71a12030v7d06501f6467f93@mail.gmail.com> <1e16a9ed0809101422p6a58304dxaa1a92847109a518@mail.gmail.com> <48C8EC48.6080507@eu.citrix.com> <48C9367B.6090003@eu.citrix.com> <1e16a9ed0809110835p73165150t3f78d75b2f2ca8eb@mail.gmail.com> <48C9548C.4060709@eu.citrix.com> <48C962D8.5030102@eu.citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 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: George Dunlap Cc: Muli Ben-Yehuda , deshantm@gmail.com, Gianluca Guida , xen-devel mailing list , Anthony Liguori List-Id: xen-devel@lists.xenproject.org George Dunlap wrote: > Ah, that's the problem... Linux seems to have changed the location of > the 1:1 map. Gianluca's using an older kernel, where it's at > 0xffff810000000000, but this trace has it at 0xffff880000000000, so > the "guess" heuristic is missing. > > Jereme, is this a permanent long-term move, or is it going to be > something random? I.e., should we just add a new heuristic "guess" at > this address, or do we need to do something more complicated? > It's a permanent move. I moved it up to 0xffff880000000000 to leave space for Xen when running as a PV kernel, but there's no reasonable way to make it variable so the linear map will be there regardless of what mode the kernel is operating in. J