From owner-cvs-all Thu Feb 6 14: 2:12 2003 Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5618337B401; Thu, 6 Feb 2003 14:02:10 -0800 (PST) Received: from canning.wemm.org (canning.wemm.org [192.203.228.65]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0914743F75; Thu, 6 Feb 2003 14:02:10 -0800 (PST) (envelope-from peter@wemm.org) Received: from wemm.org (localhost [127.0.0.1]) by canning.wemm.org (Postfix) with ESMTP id EDA882A89E; Thu, 6 Feb 2003 14:02:09 -0800 (PST) (envelope-from peter@wemm.org) X-Mailer: exmh version 2.5 07/13/2001 with nmh-1.0.4 To: phk@freebsd.org Cc: Bruce Evans , "Greg 'groggy' Lehey" , all-committers@freebsd.org, legacy-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/sys/i386/include clock.h src/sys/i386/i386 tsc.c In-Reply-To: <52866.1044516029@critter.freebsd.dk> Date: Thu, 06 Feb 2003 14:02:09 -0800 From: Peter Wemm Message-Id: <20030206220209.EDA882A89E@canning.wemm.org> Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG phk@freebsd.org wrote: > In message <20030206174018.R72201-100000@gamplex.bde.org>, Bruce Evans writes : > > >However, precise measurements of these clocks turn out to be essentially > >useless except probably for phk's nonstandard hardware, since the > >accuracy of these clocks is much worse than their precision. Drift of > >10-100 parts per million for a 10 degree temperature change is normal. > >So calibrations more precise than this are not useful. > > Actually, things have improved, and motherboard crystals are now > generally no worse than +/-1 PPM/K. For newer motherboards. :-) Cheers, -Peter -- Peter Wemm - peter@wemm.org; peter@FreeBSD.org; peter@yahoo-inc.com "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message