From owner-freebsd-smp Fri Nov 5 11: 8: 4 1999 Delivered-To: freebsd-smp@freebsd.org Received: from gndrsh.dnsmgr.net (GndRsh.dnsmgr.net [198.145.92.4]) by hub.freebsd.org (Postfix) with ESMTP id B454714BEA for ; Fri, 5 Nov 1999 11:08:00 -0800 (PST) (envelope-from freebsd@gndrsh.dnsmgr.net) Received: (from freebsd@localhost) by gndrsh.dnsmgr.net (8.9.3/8.9.3) id LAA57990; Fri, 5 Nov 1999 11:03:18 -0800 (PST) (envelope-from freebsd) From: "Rodney W. Grimes" Message-Id: <199911051903.LAA57990@gndrsh.dnsmgr.net> Subject: Re: Dual Celeron + FreeBSD? In-Reply-To: from "Eric J. Schwertfeger" at "Nov 5, 1999 10:47:30 am" To: ejs@bfd.com (Eric J. Schwertfeger) Date: Fri, 5 Nov 1999 11:03:17 -0800 (PST) Cc: adams@digitalspark.net (Adam Strohl), doconnor@gsoft.com.au (Daniel O'Connor), darrylo@sr.hp.com (Darryl Okahata), freebsd-smp@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL54 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > On Fri, 5 Nov 1999, Rodney W. Grimes wrote: > > > > I've done make buildworld's on both my dual Celeron and my dual PPro (the > > > ones with 512K cache). The difference between single and dual celeron is > > > minimal, about 10%. On the dual PPro machine, the speed improvement, > > > using the same disk subsystem, was 80%. Yes, on processes that aren't > > > memory intensive, dual Celerons rock. In fact, on most things, I see > > > closer to 40-50% improvement with dual Celerons, the make buildworld is > > > rather memory intensive. > > > > Actually make buildworld is disk intensive... SMP plain out does not > > seem to help it much, unless of course you run a non-standard make > > world with -pipe, which then does make the memory bandwidth demand > > higher, and if both sides of the pipe just happen to get split accross > > 2 processors it causes the small cache to be ineffective and the memory > > system to be a major stall point. > > Can't remember if I was using -pipe, this was a default 3.2 install, > except that I'm pretty sure I was using soft updates. I may have been, > because the HD lights would only flicker every few seconds, so it > definitely wasn't disk bound. I had /usr/src, /usr/obj, and /tmp all on > seperate spindles (each on a 4GB 7200 RPM SCSI drive). Given other > people's comments, I'd really expect more than the 10% that I saw. Soft updates shifts the bottleneck from disk to memory. We run our baseline comparison testing using unmodified in anyway installs from CDROM of the latest version of -release. -- Rod Grimes - KD7CAX @ CN85sl - (RWG25) rgrimes@gndrsh.dnsmgr.net To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message