From owner-freebsd-current@FreeBSD.ORG Tue Sep 2 00:17:06 2003 Return-Path: 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 D2FB716A4BF; Tue, 2 Sep 2003 00:17:06 -0700 (PDT) Received: from rwcrmhc12.comcast.net (rwcrmhc12.comcast.net [216.148.227.85]) by mx1.FreeBSD.org (Postfix) with ESMTP id C2C3943FBD; Tue, 2 Sep 2003 00:17:05 -0700 (PDT) (envelope-from DougB@freebsd.org) Received: from master.dougb.net (12-234-22-23.client.attbi.com[12.234.22.23](untrusted sender)) by comcast.net (rwcrmhc12) with SMTP id <20030902071705014000t4v1e>; Tue, 2 Sep 2003 07:17:05 +0000 Date: Tue, 2 Sep 2003 00:17:04 -0700 (PDT) From: Doug Barton To: "Matthew D. Fuller" In-Reply-To: <20030902070502.GQ38141@over-yonder.net> Message-ID: <20030902001511.Y6074@znfgre.qbhto.arg> References: <41076.1062480964@critter.freebsd.dk> <20030901233731.U6074@znfgre.qbhto.arg> <20030902070502.GQ38141@over-yonder.net> Organization: http://www.FreeBSD.org/ X-message-flag: Outlook -- Not just for spreading viruses anymore! MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: Poul-Henning Kamp cc: freebsd-current@freebsd.org Subject: Re: swapon vs savecore dilemma X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Sep 2003 07:17:06 -0000 On Tue, 2 Sep 2003, Matthew D. Fuller wrote: > On Tue, Sep 02, 2003 at 12:58:40AM -0600 I heard the voice of > Scott Long, and lo! it spake thus: > > > > I still think that the real problem is in running swapon before > > savecore. In 99% of the cases out there, RAM scales with storage, > > so I really can't imaging fsck needing to swap, and certainly not > > in it's 'preen-before-background' mode. > > Note also that (last I heard, anyway) this is often "worked around", or > non-issued, by us allocating swap from the "bottom" of the partition up, > and coredumps happening from the "top" down. So, if you've got 512 megs > of swap, and 128 megs of ram, you'd need to use 384 megs of swap (+/- > housekeeping) before you corrupted your core. I agree that this _should_ be the case, but I've seen the advice of putting in swap space equal to the amount of memory often enough to make me nervous that this is a safe assumption. Doug -- This .signature sanitized for your protection