From owner-freebsd-stable Mon May 8 20:38:52 2000 Delivered-To: freebsd-stable@freebsd.org Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by hub.freebsd.org (Postfix) with ESMTP id 3306937BD5F; Mon, 8 May 2000 20:38:43 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: (from grog@localhost) by freebie.lemis.com (8.9.3/8.9.0) id NAA77643; Tue, 9 May 2000 13:04:23 +0930 (CST) Date: Tue, 9 May 2000 13:04:23 +0930 From: Greg Lehey To: "Jeffrey J. Mountin" Cc: freebsd-stable@FreeBSD.ORG, freebsd-hackers@FreeBSD.ORG Subject: Re: Debugging Kernel/System Crashes, can anyone help?? Message-ID: <20000509130423.Q75157@freebie.lemis.com> References: <4.3.2.20000503221040.02051d40@207.227.119.2> <20000503185936.E72341@ethereal.net> <20000504095941.B18453@freebie.lemis.com> <200005040124.VAA55655@account.abs.net> <20000504111136.B22025@freebie.lemis.com> <20000503185936.E72341@ethereal.net> <20000504114013.E22025@freebie.lemis.com> <4.3.2.20000503221040.02051d40@207.227.119.2> <20000506073852.E37507@freebie.lemis.com> <4.3.2.20000506175851.00ae9b50@207.227.119.2> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0pre2i In-Reply-To: <4.3.2.20000506175851.00ae9b50@207.227.119.2> Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-418-838-708 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Saturday, 6 May 2000 at 18:15:15 -0500, Jeffrey J. Mountin wrote: > At 07:38 AM 5/6/00 +0930, Greg Lehey wrote: >> On Thursday, 4 May 2000 at 17:00:35 -0500, Jeffrey J. Mountin wrote: >>> At 11:40 AM 5/4/00 +0930, Greg Lehey wrote: >>>> There's a separate issue about whether to build kernels with debug >>>> symbols by default. That takes a lot more space (30 MB as compared to >>>> about 8). But if you have a debug kernel, I don't see any reason to >>>> install a stripped version. >>> >>> Running the non-stripped kernel uses more memory >> >> No, this isn't correct, not with ELF. >> >>> and isn't there also a performance issue. >> >> No. > > Thanks for clarifying that, but were either memory or performance an > issue back in the AOUT days? I seem to recall something to that > point, but might be wrong. Yes, if you booted an a.out debug kernel, you ended up loading the entire kernel, including debug symbols, into memory. >>> Also what is gained by running it, >> >> Disk space. > > Then it's an issue of disk layout. I use a 100 MB root, which should be > good for number of years to come and /var is not a part of the root > partition. IMO space is (or should be) a non-issue or at least should be > for most. YMMV and don't care to beat that horse some once more. Sure, that's one of the issues I mentioned. But I think 100 MB is fine for a couple of debug kernels. My main machine (which I don't use for debugging) has only 30 MB in the root file system. >>> as long as you have the complimentary debug kernel in /var/crash (or >>> wherever) for the stripped boot kernel. >> >> It's the one that savecore saves, and there's more opportunity for >> using the wrong debug kernel for dump analysis. > > True, but then one would hope someone doing analysis would know > better. It's not a question of knowing better, it's a question of honest-to-god mistakes. I make enough of them myself. > Maybe there should be an "make install debug" that would either > install the debug version instead of the stripped version *or* > install it in /var/crash. Indeed, there *is* a make install.debug (note spelling) which installs the debug version instead of the stripped version. > If there are no memory or performance issues with the debug kernel, > then I wouldn't mind it being installed as the default. Then those > that wish to strip it may do so. As always the point is who gains > changing the current method. I tried this a while back. There was a lot of resistance. Greg -- Finger grog@lemis.com for PGP public key See complete headers for address and phone numbers To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message