From owner-freebsd-current Mon Oct 12 12:30:44 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id MAA20926 for freebsd-current-outgoing; Mon, 12 Oct 1998 12:30:44 -0700 (PDT) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from tim.xenologics.com (tim.xenologics.com [194.77.5.24]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id MAA20903 for ; Mon, 12 Oct 1998 12:30:37 -0700 (PDT) (envelope-from seggers@semyam.dinoco.de) Received: (from uucp@localhost) by tim.xenologics.com (8.8.5/8.8.8) with UUCP id VAA19441; Mon, 12 Oct 1998 21:28:34 +0200 (MET DST) Received: from semyam.dinoco.de (semyam.dinoco.de [127.0.0.1]) by semyam.dinoco.de (8.9.1/8.8.8) with ESMTP id VAA26752; Mon, 12 Oct 1998 21:27:58 +0200 (CEST) (envelope-from seggers@semyam.dinoco.de) Message-Id: <199810121927.VAA26752@semyam.dinoco.de> To: Alfred Perlstein Cc: Zach Heilig , current@FreeBSD.ORG, seggers@semyam.dinoco.de Subject: Re: wd, crash dumps and strange geometries (was: Re: bitten 3 times already. ) In-reply-to: Your message of "Mon, 12 Oct 1998 20:25:16 +0200." <199810121825.UAA04383@semyam.dinoco.de> Date: Mon, 12 Oct 1998 21:27:56 +0200 From: Stefan Eggers Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > you use the geometry for 15 heads the CHS addressing will be wrong and > maybe this is what somehow caused the failure you saw. I looked at where exactly the system puts the crash dump. At the *end* of the partition you give it. With 15 heads you get to larger cylinders (nearer your /usr) faster than with the correct 16 heads so what happens I suppose is that it overwrites most of the start of /usr due to taking the wrong geometry. I am pretty convinced that using the same mode for crash dumps as for normal block reads/writes prevents this kind of disaster. Maybe some- one can commit a fix? Or shall I send a PR with my suggestion in- stead? Why was it that one put the at partitions end in the first place? Am I right when I guess it was so that one could enable swapping, do a little bit of it and still get reasonable crash dumps? Stefan. -- Stefan Eggers Lu4 yao2 zhi1 ma3 li4, Max-Slevogt-Str. 1 ri4 jiu3 jian4 ren2 xin1. 51109 Koeln Federal Republic of Germany To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message