From owner-freebsd-questions Mon Nov 26 9:10:39 2001 Delivered-To: freebsd-questions@freebsd.org Received: from blackhelicopters.org (geburah.blackhelicopters.org [209.69.178.18]) by hub.freebsd.org (Postfix) with ESMTP id 4D62237B41A for ; Mon, 26 Nov 2001 09:10:34 -0800 (PST) Received: (from mwlucas@localhost) by blackhelicopters.org (8.11.6/8.11.6) id fAQHAR342285; Mon, 26 Nov 2001 12:10:27 -0500 (EST) (envelope-from mwlucas) Date: Mon, 26 Nov 2001 12:10:27 -0500 From: Michael Lucas To: Anthony Atkielski Cc: FreeBSD Questions Subject: Re: Calculating swap file size Message-ID: <20011126121027.A42249@blackhelicopters.org> References: <00e201c1769b$a36bbd40$0a00000a@atkielski.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <00e201c1769b$a36bbd40$0a00000a@atkielski.com>; from anthony@freebie.atkielski.com on Mon, Nov 26, 2001 at 05:58:53PM +0100 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 Well, it depends on what you're doing. If you're doing kernel debugging, 800M of swap will not let you dump a kernel image to disk. This would be bad. If you're a user, 800M of swap should be more than enough. I have 1G of RAM, and never even touch swap. FreeBSD only uses swap when it runs out of physical memory. Once swap is allocated, however, it tends to hang on to it. There's a FAQ entry about this. On Mon, Nov 26, 2001 at 05:58:53PM +0100, Anthony Atkielski wrote: > Since memory isn't very expensive these days, I'm thinking of adding more RAM to > my FreeBSD machine; it has 256 MB, but I was thinking of going to 1 GB, which is > the capacity of this machine. Currently, I have a 800 MB swap partition (or is > it a slice?--I know it's not a filesystem) defined. Is this enough for 1 GB of > RAM? Is there any kind of strong correlation between RAM size and swap file > size that I have to be concerned about? Does FreeBSD resort to swap only when > RAM is exhausted, or does it have to use the swap file all the time (as in a > one-to-one VM mapping scheme)? If the swap file is of less than optimal size, > what happens? > > I looked at the swapinfo command and it shows 0% of the swap file used (the > system is not heavily loaded by any measure). > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message -- Michael Lucas mwlucas@blackhelicopters.org http://www.blackhelicopters.org/~mwlucas/ Big Scary Daemons: http://www.oreillynet.com/pub/q/Big_Scary_Daemons To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message