From owner-freebsd-questions Mon Jul 2 10:37:17 2001 Delivered-To: freebsd-questions@freebsd.org Received: from sydney.worldwide.lemis.com (pixpat.austin.ibm.com [192.35.232.241]) by hub.freebsd.org (Postfix) with ESMTP id 5585A37B405 for ; Mon, 2 Jul 2001 10:37:11 -0700 (PDT) (envelope-from grog@sydney.worldwide.lemis.com) Received: (from grog@localhost) by sydney.worldwide.lemis.com (8.11.3/8.9.3) id f621DRm00472; Sun, 1 Jul 2001 20:13:27 -0500 (CDT) (envelope-from grog) Date: Sun, 1 Jul 2001 20:13:27 -0500 From: Greg Lehey To: "Andrew C . Hornback" , Alexandr Alov , Linh Pham Cc: freebsd-questions@FreeBSD.org Subject: Number of processors for SMP (was: Question of day.) Message-ID: <20010701201327.B418@sydney.worldwide.lemis.com> References: <01063023314202.14971@max.myhome.ru> <01063023314202.14971@max.myhome.ru> <004801c101d3$ba4cb100$0e00000a@tomcat> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <004801c101d3$ba4cb100$0e00000a@tomcat>; from hornback@wireco.net on Sat, Jun 30, 2001 at 10:15:41PM -0400 Organization: The FreeBSD Project Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-418-838-708 WWW-Home-Page: http://www.FreeBSD.org/ X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Saturday, 30 June 2001 at 22:15:41 -0400, Andrew C. Hornback wrote: > On Saturday, June 30, 2001 2:54 PM, Linh Pham wrote: >> To: Alexandr Alov >> Cc: freebsd-questions@FreeBSD.org >> Subject: Re: Question of day. >> >> >> On 2001-06-30, Alexandr Alov scribbled: >> >> # What maximum quantity of processors can support FreeBSD 4.3 ? >> >> I've seen FreeBSD 4.x installations with four Intel Xeon processors... >> but with the current SMP code, you probably won't be able to take >> complete advantage of all four processors. SMPng in FreeBSD 5.x is >> supposed to take SMP performance to a much higher notch. >> >> Haven't been able to get my hands on a eight-way server yet :) > > I've seen FreeBSD 4.2-Release running on a 6 way machine, and this was > about 5 months ago. Worked like a charm, and a good thing too, since I'm > building one of these "monsters" myself... > > Given the technology that's out there, the most IA processors > I've ever heard of in a machine would be the new Unisys CMP-7000 > (Model number might be wrong) with up to either 32 or 64 processors > per box... needless to say, it'll be a while before I get one of > those as a workstation. *evil grin* I don't think there's any particular hard limit in the number of processors. In general, the incremental benefit of adding more processors will diminish as you increase the number. I'd guess that 8 processors will work, but that the 32/64 processor machines will not work for reasons not directly related to the number of processors. On Saturday, 30 June 2001 at 23:21:33 +0400, Alexandr Alov wrote: >> I've seen FreeBSD 4.x installations with four Intel Xeon processors... >> but with the current SMP code, you probably won't be able to take >> complete advantage of all four processors. SMPng in FreeBSD 5.x is >> supposed to take SMP performance to a much higher notch. >> >> Haven't been able to get my hands on a eight-way server yet :) > > Thank for the answer. > Only four? > In general that is necessary eight. > How with such quantity ? It depends on what you want to do with them. The real issue is contention for the kernel. If you are doing compute-bound work, the additional CPUs will be very useful. If you're I/O bound, you'll quickly reach the point of diminishing returns. On Saturday, 30 June 2001 at 12:25:31 -0700, Linh Pham wrote: > On 2001-06-30, Alexandr Alov scribbled: > > # Thank for the answer. > # Only four? > > You can probably get FreeBSD to install on 8+ processor servers, but > with my experience... I have only worked with machines with four > processors. > > # In general that is necessary eight. > > Remember, the standard version of Windows 2000 only handles up to four > processors ;-) Well, I didn't know that, but I can't see that it's very relevant. -- When replying to this message, please copy the original recipients. If you don't, I may ignore the reply. For more information, see http://www.lemis.com/questions.html See complete headers for address and phone numbers To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message