From owner-freebsd-smp Sun Sep 14 02:55:53 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id CAA03338 for smp-outgoing; Sun, 14 Sep 1997 02:55:53 -0700 (PDT) Received: from usr06.primenet.com (tlambert@usr06.primenet.com [206.165.6.206]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id CAA03333 for ; Sun, 14 Sep 1997 02:55:51 -0700 (PDT) Received: (from tlambert@localhost) by usr06.primenet.com (8.8.5/8.8.5) id CAA14249; Sun, 14 Sep 1997 02:55:48 -0700 (MST) From: Terry Lambert Message-Id: <199709140955.CAA14249@usr06.primenet.com> Subject: Re: SMP in FreeBSD 3.x.x To: Shimon@i-connect.net (Simon Shapiro) Date: Sun, 14 Sep 1997 09:55:48 +0000 (GMT) Cc: tlambert@primenet.com, freebsd-smp@freebsd.org, missmanp@milo.cfw.com In-Reply-To: from "Simon Shapiro" at Sep 14, 97 00:30:34 am X-Mailer: ELM [version 2.4 PL23] Content-Type: text Sender: owner-freebsd-smp@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > When I worked at that awful place, we actually computed how many processors > one could put on the P6 bus. The number was much, much lower than 30. > Our number was based on trying to have the CPUs access memory and I/O. > With respect, that's because the people designing the access paradigms weren't very clever. It's possible to allocate from a global pool to a per processor pool. If I'm trying to allocate out of a per processor pool, then I don't have to contend with other processors to do the allocation. In effect, this is a virtual NUMA. See the Dynix paper: Efficient Kernel Memory Allocation on Shared Memory Multiprocessors McKenney, P.E. and Swignline , J. Proceeding of Winter 1993 Usenix Technical Conference Jan 1993, pages 295-303 Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.