From mboxrd@z Thu Jan 1 00:00:00 1970 From: tgh Subject: Re: how many processors does xen support in hardware? Date: Sun, 26 Aug 2007 21:26:20 +0800 Message-ID: <46D17F7C.5000909@ncic.ac.cn> References: <200708242345.09576.rautelap@gmail.com> <46CFDA55.5070609@ncic.ac.cn> <46d0121a.0589300a.5f14.061c@mx.google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <46d0121a.0589300a.5f14.061c@mx.google.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: Mats Petersson Cc: xen-devel List-Id: xen-devel@lists.xenproject.org Thank you for your reply and did you take any scalability experiments for xen under hardware=20 platform with 16cpus or more cpus for datacenter application or any=20 other applications? and what about the performance of xen ,comparing=20 with the native linux? Thanks Mats Petersson =E5=86=99=E9=81=93: > At 08:29 25/08/2007, you wrote: >> hi >> did someone make the experiment for the xen's scalability in the aspec= t >> of the cpu number supported? and what about the performence with 16 cp= us >> , 32 cpus , and 64cpus, say ,comparing with the native linux? > > > This would be very dependant on the workload type - something that=20 > does a lot of page-table updates will be more affected by "xen=20 > overhead" than something that does no page-table updates. Other than=20 > that, a para-virtual guest should be fairly close to the native setup. > > Of course, finding machines with more than 32 cores is pretty=20 > difficult, as 32 takes 8 sockets of quad-cores, and that's pretty much=20 > the limit on "standard" motherboards - and even those are pretty darn=20 > expensive. > > --=20 > Mats > > > > >> pradeep singh $B> > On Friday 24 August 2007 23:34:27 Keir Fraser wrote: >> > >> >> Oh, right, yes that is Linux's configurable maximum (itself fairly >> >> arbitrary really). You can't actually use that number on Xen, so=20 >> don't set >> >> it so high. Simple really. :-) >> >> >> > >> > Simple?...heh :-) >> > I'll keep that in mind. >> > >> > thanks for insight. >> > --pradeep >> > >> >> -- Keir >> >> >> >> On 24/8/07 19:00, "pradeep singh" wrote: >> >> >> >>> On Friday 24 August 2007 20:19:07 Keir Fraser wrote: >> >>> >> >>>> Where did you get this number 255 from? >> >>>> >> >>> Sorry i meant, while i compile the xen kernel i can configure=20 >> kernel upto >> >>> a max of 255. right? >> >>> >> >>> And i guess that means the number of CPUs you can compile your=20 >> SMP kernel >> >>> to work with. >> >>> what did i miss? :-/ >> >>> >> >>> thanks >> >>> --pradeep >> >>> >> >>> >> >>>> K. >> >>>> >> >>>> >> > [snip] >> > >> > >> > >> > _______________________________________________ >> > Xen-devel mailing list >> > Xen-devel@lists.xensource.com >> > http://lists.xensource.com/xen-devel >> > >> > >> > . >> > >> > >> >> >> _______________________________________________ >> Xen-devel mailing list >> Xen-devel@lists.xensource.com >> http://lists.xensource.com/xen-devel > > > > . >