From owner-freebsd-hackers@FreeBSD.ORG Sat Oct 2 00:16:55 2004 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5B5B216A4CE for ; Sat, 2 Oct 2004 00:16:55 +0000 (GMT) Received: from w2xo.jcdurham.com (18.gibs5.xdsl.nauticom.net [209.195.184.19]) by mx1.FreeBSD.org (Postfix) with ESMTP id C073A43D3F for ; Sat, 2 Oct 2004 00:16:54 +0000 (GMT) (envelope-from durham@jcdurham.com) Received: from dhcp13.home.jcdurham.com (dhcp13.home.jcdurham.com [192.168.5.13]) by w2xo.jcdurham.com (8.12.11/8.11.6) with ESMTP id i920GqXp077233; Fri, 1 Oct 2004 20:16:52 -0400 (EDT) (envelope-from durham@jcdurham.com) From: Jim Durham To: freebsd-hackers@freebsd.org Date: Fri, 1 Oct 2004 20:16:51 -0400 User-Agent: KMail/1.7 References: <200410011636.i91GaYgC093428@ambrisko.com> In-Reply-To: <200410011636.i91GaYgC093428@ambrisko.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200410012016.51415.durham@jcdurham.com> Subject: Re: Sudden Reboots X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 02 Oct 2004 00:16:55 -0000 On Friday 01 October 2004 12:36 pm, Doug Ambrisko wrote: > Jim Durham writes: > | I have had this problem now with at least 3 FreeBSD servers over a period > | of about 2 years. I had put it down to some hardware problem but it seems > | to be too much of a coincidence with 3 different machines doing the same > | thing. > | > | The first time was when I put 4.5-RELEASE on a brand new Dell Poweredge > | 2650. I ran it on the bench for a week or so, then decided all was well > | and put it in the server rack and started doing the company's email > | service on it. After a few weeks, it suddenly would 'reboot' for no > | apparent reason. No log entries, nothing at all except the usual stuff in > | /var/log/messages about '/ was not unmounted correctly', etc. Just like > | you had pulled the power plug. > > How much memory are in these system?. The Dell is a Dual Xeon 2650 with 2gb or Ram. The ISP's box has only 256 megs or ram and the business customer's box has 512. > If you have 3G or more you end > up with very little left for the kernel in the 2G space Can you elaborate on why this is? > . You can > monitor how much space you have left by compile a debug kernel then > as root: > gdb -k kernel.debug /dev/mem > print ((unsigned int)virtual_end)-((unsigned int)kernel_vm_end) > This should probably be made into a sysctl so it can be montored > better. > > If you only have a few meg. left it doesn't take many processes to > fork etc. then you machine blows up. The bge driver for example takes > 4M each for the jumbo packet handling. You can recover some of this > memory via loader.conf tunables or bump KVA_PAGES in your kernel > config file. Still once this memory is put into the zone allocator > (vmstat -z) in -stable it is gone from the system even if that bucket > isn't fully used or needed :-( What would you expect to see in the logs on such a scenario? I'm surprised to see nothing. > > Ironically the more memory you put in a system the less you can do with > the system! > > A lot of people are starting to run into this problem since large memory > machines are cheap. Well, I don't think 2gb is large by your standards? > > Doug A. -- -Jim