From owner-freebsd-smp Tue Sep 21 20:22:38 1999 Delivered-To: freebsd-smp@freebsd.org Received: from shell.webmaster.com (mail.webmaster.com [209.133.28.73]) by hub.freebsd.org (Postfix) with ESMTP id 33CF414F4D; Tue, 21 Sep 1999 20:22:33 -0700 (PDT) (envelope-from davids@webmaster.com) Received: from whenever ([209.133.29.2]) by shell.webmaster.com (Post.Office MTA v3.5.3 release 223 ID# 0-12345L500S10000V35) with SMTP id com; Tue, 21 Sep 1999 20:22:32 -0700 From: "David Schwartz" To: "Brian F. Feldman" , "Luoqi Chen" Cc: , Subject: RE: Testers please! Date: Tue, 21 Sep 1999 20:22:32 -0700 Message-ID: <000001bf04a9$b50ebf90$021d85d1@youwant.to> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook 8.5, Build 4.71.2377.0 In-Reply-To: Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2314.1300 Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > One question comes to mind: is there a way that the TSCs could become > desynchronized somehow? Even though all CPUs run at the same frequency, > isn't there a strong possibility for slight frequency deviation since > we use crystal oscillation instead of a more accurate atomic breakdown > for regulation, or am I just smoking crack? All CPUs should be clocked off of the same frequency multiplier off of the same crystal, so it _should_ be impossible for the TSCs to drift apart due to that. I guess it might be theoretically possible that something might cause the TSCs to drift. Perhaps something crazy with APM and/or SMM. It should be tested. It should also be tested that they begin at the same place. Perhaps processors might take different amount of times to 'come out of' reset. I wouldn't assume anything. DS To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message