From owner-freebsd-questions Mon Mar 24 9:59:57 2003 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id F285937B401 for ; Mon, 24 Mar 2003 09:59:54 -0800 (PST) Received: from mired.org (ip68-97-54-220.ok.ok.cox.net [68.97.54.220]) by mx1.FreeBSD.org (Postfix) with SMTP id 2B96543FA3 for ; Mon, 24 Mar 2003 09:59:53 -0800 (PST) (envelope-from mwm-dated-1048960792.251d4a@mired.org) Received: (qmail 92874 invoked from network); 24 Mar 2003 17:59:52 -0000 Received: from localhost.mired.org (HELO guru.mired.org) (127.0.0.1) by localhost.mired.org with SMTP; 24 Mar 2003 17:59:52 -0000 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15999.18326.297880.599596@guru.mired.org> Date: Mon, 24 Mar 2003 11:59:50 -0600 To: The Anarcat Cc: freebsd-questions@freebsd.org Subject: Re: crashdumping on massive amounts of RAM In-Reply-To: <20030324174332.GB831@lenny.anarcat.ath.cx> References: <20030324174332.GB831@lenny.anarcat.ath.cx> X-Mailer: VM 7.07 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`; h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ From: Mike Meyer X-Delivery-Agent: TMDA/0.71 (Hoop, Jr.) X-Spam-Status: No, hits=-19.6 required=5.0 tests=IN_REP_TO,QUOTED_EMAIL_TEXT,REFERENCES,REPLY_WITH_QUOTES autolearn=ham version=2.50 X-Spam-Level: X-Spam-Checker-Version: SpamAssassin 2.50 (1.173-2003-02-20-exp) Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG In <20030324174332.GB831@lenny.anarcat.ath.cx>, The Anarcat typed: > I am fortunate enough to have a box with a lot (by my standards) of > RAM: > > real memory = 1207877632 (1151 MB) > avail memory = 1166782464 (1112 MB) > > Now the problem I have is I'd like to debug the panic()s I'm seeing > now and then on this box, since I'm running 5.0. :) But it seems I > need at least as much swap as I need RAM to do this. > > So I just want to make sure there is no other way to crashdump this > RAM than making a gigantic 1GB swap area. The worst is that I really > don't need 1GB of *swap*!! 1GB of RAM is fine. All processes run in > main memory, but 1GB of swap? That would *suck*. ;) I have 250MB right > now and I already think it's too much. > > Any brilliant ideas to work around this? Yes - enable the kernel debugging option (DDB) on the kernel, and debug the running system when it panics. As for your swap partition - the same thing happens when you run out of virtual memory either way: processes start dieing. Having a little swap lets you get a warning of that because you'll start paging things out which would otherwise live in memory. Unless you're planning on setting up a warning system that watches for paging activity and notifies you so you can do something about it, there's probably not much point in having 250MB of swap on a system with a gigabyte of ram. In your shoes, I'd seriously consider running without swap. On the other hand, disk space is so cheap that I always have lots of swap. Something about the days when I used to recompile LISP systems on memory-starved machines.... http://www.mired.org/consulting.html Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message