From owner-freebsd-current@FreeBSD.ORG Tue Jul 13 04:36:10 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 4EAF916A4CE; Tue, 13 Jul 2004 04:36:10 +0000 (GMT) Received: from postal2.es.net (postal2.es.net [198.128.3.206]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2377643D2D; Tue, 13 Jul 2004 04:36:10 +0000 (GMT) (envelope-from oberman@es.net) Received: from ptavv.es.net ([198.128.4.29]) by postal2.es.net (Postal Node 2) with ESMTP (SSL) id IBA74465; Mon, 12 Jul 2004 21:36:09 -0700 Received: from ptavv (localhost [127.0.0.1]) by ptavv.es.net (Tachyon Server) with ESMTP id 57A385D08; Mon, 12 Jul 2004 21:36:08 -0700 (PDT) To: Johan Pettersson In-reply-to: Your message of "Mon, 12 Jul 2004 22:56:12 +0200." <20040712225612.3ba37729.manlix@demonized.net> Date: Mon, 12 Jul 2004 21:36:08 -0700 From: "Kevin Oberman" Message-Id: <20040713043608.57A385D08@ptavv.es.net> cc: freebsd-current@freebsd.org cc: Robert Watson cc: avleeuwen@piwebs.com cc: skywizard@mybsd.org.my Subject: Re: Native preemption is the culprit [was Re: today's CURRENT lockups] X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 13 Jul 2004 04:36:10 -0000 > Date: Mon, 12 Jul 2004 22:56:12 +0200 > From: Johan Pettersson > Sender: owner-freebsd-current@freebsd.org > > > It's not currently clear what the cause is -- reports suggest that > > it's an existing bug that's getting triggered by preemption, although > > I wouldn't rule out a bug in the preemption implementation itself. > > I'm currently setting up a box with NMI to see if I can get some more > > useful information, as serial break isn't cutting it (suggesting a > > leaked spin lock or critical section). I don't have an ETA, but I'm > > guessing that we'll have some sort of resolution in the next day or > > two. If not, I guess we back out the change, or disable PREEMPTION by > > default. > > > > Robert N M Watson FreeBSD Core Team, TrustedBSD Projects > > robert@fledge.watson.org Principal Research Scientist, McAfee > > Research > > > > Okey... Im going to build a kernel with #define PREEMPTION disabled now. > Its too annoying to get lock-ups all the time. :) Shout when you have > some code to be tested. I have found the interrupt latency on a loaded system to be simply unacceptable and have backed off the code to before this change wa made. I am running: sys/sys/interrupt.h - v1.27 sys/kern/kern_intr.c - v1.110 sys/i386/i386/intr_machdep.c - v1.6 sys/kern/sched_ule.c - v1.109 and this has things back to normal. thanks to Ariff Abdullah for the list of file versions. -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634