From owner-freebsd-current Fri Aug 21 22:24:34 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id WAA27587 for freebsd-current-outgoing; Fri, 21 Aug 1998 22:24:34 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from dyson.iquest.net (dyson.iquest.net [198.70.144.127]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id WAA27566; Fri, 21 Aug 1998 22:24:27 -0700 (PDT) (envelope-from toor@dyson.iquest.net) Received: (from root@localhost) by dyson.iquest.net (8.8.8/8.8.8) id AAA19739; Sat, 22 Aug 1998 00:23:34 -0500 (EST) (envelope-from toor) Message-Id: <199808220523.AAA19739@dyson.iquest.net> Subject: Re: softupdates and smp crash In-Reply-To: <199808200641.XAA18028@usr02.primenet.com> from Terry Lambert at "Aug 20, 98 06:41:53 am" To: tlambert@primenet.com (Terry Lambert) Date: Sat, 22 Aug 1998 00:23:34 -0500 (EST) Cc: sos@FreeBSD.ORG, tlambert@primenet.com, croot@btp1da.phy.uni-bayreuth.de, regnauld@deepo.prosa.dk, current@FreeBSD.ORG, smp@FreeBSD.ORG From: "John S. Dyson" Reply-To: dyson@iquest.net X-Mailer: ELM [version 2.4ME+ PL38 (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 Terry Lambert said: > > > > So we can still say that softupdates are broken, at least for SMP. > > > > > > It would be more useful (than saying this) for people to characterize > > > the problem they are getting so that we can find a discriminitory > > > value. I suggest: > > > > I suggest reading Luoqi Chen's exelent explanation as why it breaks > > under SMP (hint: it has nothing todo with HW setups).. > > Perhaps clock speed? 8-). > > His post arrived in my mailbox after I responded to your post... > > I'm also not convinced that this is the only possible cause of > the problem; the VM code is hardly "assert" protected everywhere, > so diagnosing this thing is not trivial. Look at the VM fixes > I recently did, which killed the bugs Karl Denniger was seeing > in 75% of the cases, leaving 25% of the cases "clustered" (in his > words), indicating a seperate problem, in addition to the ones I > fixed, in a periodically executing code path. I had suspected > that this would be the case when I made the fix, since it doesn't > account for the buggy behaviour I'm personally seeing. 8-(. > I have to chime in here -- some of the "fixes" are work-arounds, and there are still underlying VM problems. It might be "good enough" for 3.0, but I would suggest preparing for some rework to find the root cause for the problem. -- John | Never try to teach a pig to sing, dyson@iquest.net | it makes one look stupid jdyson@nc.com | and it irritates the pig. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message