From owner-freebsd-current Sat Nov 23 2:57:48 2002 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 4E71E37B401 for ; Sat, 23 Nov 2002 02:57:47 -0800 (PST) Received: from mail.rpi.edu (mail.rpi.edu [128.113.22.40]) by mx1.FreeBSD.org (Postfix) with ESMTP id 87FB143EAF for ; Sat, 23 Nov 2002 02:57:46 -0800 (PST) (envelope-from drosih@rpi.edu) Received: from [128.113.24.47] (gilead.netel.rpi.edu [128.113.24.47]) by mail.rpi.edu (8.12.1/8.12.1) with ESMTP id gANAviZI198550; Sat, 23 Nov 2002 05:57:44 -0500 Mime-Version: 1.0 X-Sender: drosih@mail.rpi.edu Message-Id: In-Reply-To: <3DDF5106.7469FBA@mindspring.com> References: <3DDF5106.7469FBA@mindspring.com> Date: Sat, 23 Nov 2002 05:57:43 -0500 To: Terry Lambert From: Garance A Drosihn Subject: Re: "A"utodefaults in disklabel on 5.0dp2 install Cc: current@FreeBSD.org Content-Type: text/plain; charset="us-ascii" ; format="flowed" X-Scanned-By: MIMEDefang 2.3 (www dot roaringpenguin dot com slash mimedefang) Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG At 1:57 AM -0800 11/23/02, Terry Lambert wrote: >Garance A Drosihn wrote: >> This is something I noticed while installing 5.0-dp2. I'm not sure > > how much we'd want to change it. > >The default swap size calculation is done on the basis of a multiple >of the physical memory size. Specifically, the physical memory may >be completely consumed by kernel structures, up to the KVA size, and >therefore in the case of a system dump, it can require up to the >size of the physical meory, plus 64K, at a bare minimum for a >successful system dump. Hmm. I hadn't really thought much about the specifics of what is needed. I was just wondering if we might want to think about the "auto size" algorithm a bit more. >So even if you were to reduce the swap size, you should not reduce >it below 768M + 64K. Well, I can see that the "auto default" partition mechanism should probably take that into account too. I'm just saying that the current algorithm gives the user (any generic user, not me specifically) a useless result. It would be nice if it came up with more usable sizes. >You will, of course, agree that a prerelease named "DP2" should >have the ability to successfully system dump, as that is one of >the primary reasons it's being handed out: to catch problems, and >to provide detailed bug reports about them, sufficient to correct >them before the official release. Well, I mentioned this now with an eye towards 5.0-release, although I realize my original message didn't indicate that. This same issue comes up when installing recent releases from 4-stable. My point is that the resulting partition sizes (in this case) are unusable. There is no point in worrying about the ability to save a system dump on a system where the initial install has pretty close to zero chance of succeeding. Let me repeat that I'm not sure how much we'd want to change it. I just wanted to point out how the current algorithm behaves when given this particular combination of disk and memory sizes. -- Garance Alistair Drosehn = gad@gilead.netel.rpi.edu Senior Systems Programmer or gad@freebsd.org Rensselaer Polytechnic Institute or drosih@rpi.edu To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message