From owner-freebsd-current Thu Sep 7 17:48:36 2000 Delivered-To: freebsd-current@freebsd.org Received: from pike.osd.bsdi.com (pike.osd.bsdi.com [204.216.28.222]) by hub.freebsd.org (Postfix) with ESMTP id 8FFE737B422 for ; Thu, 7 Sep 2000 17:48:34 -0700 (PDT) Received: (from jhb@localhost) by pike.osd.bsdi.com (8.9.3/8.9.3) id RAA26766; Thu, 7 Sep 2000 17:48:07 -0700 (PDT) (envelope-from jhb) From: John Baldwin Message-Id: <200009080048.RAA26766@pike.osd.bsdi.com> Subject: Re: microuptime() went backwards In-Reply-To: <20000908101001.G83632@wantadilla.lemis.com> from Greg Lehey at "Sep 8, 2000 10:10:02 am" To: Greg Lehey Date: Thu, 7 Sep 2000 17:48:06 -0700 (PDT) Cc: Steve Ames , freebsd-current@FreeBSD.ORG X-Mailer: ELM [version 2.4ME+ PL68 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Greg Lehey wrote: > On Thursday, 7 September 2000 at 17:28:02 -0700, John Baldwin wrote: > > Steve Ames wrote: > >> Just upgraded to -CURRENT as of about noon (EST) today. At reboot > >> I got a lot of these: > >> > >> microuptime() went backwards (1.7682417 -> 1.997434) > >> > >> I recall reading in -current earlier this week that someone was > >> looking for victims getting this. What further information can I provide? > > > > This is a SMPng issue on UP machines. > > Yes, but it's not the only cause. We've also seen it on pre-SMPng > stuff, and Athlons seem to be particularly capable of doing it. phk > is looking at it at the moment, and he has an idea what's causing it. > > I'd guess, however, that this *is* the SMPng problem. It's subtly > different from other manifestations in that the first time typically > has 7 digits after the decimal point. Most definitely an SMPng issue. If you take a SMP machine and compile a UP and an SMP kernel on it, the SMP kernel will boot fine, whereas the UP kernel will generate these warnings. > Greg > -- > Finger grog@lemis.com for PGP public key > See complete headers for address and phone numbers -- John Baldwin -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.cslab.vt.edu/~jobaldwi/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message