From owner-freebsd-bugs Tue Dec 31 4:27:27 2002 Delivered-To: freebsd-bugs@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2635E37B401 for ; Tue, 31 Dec 2002 04:27:26 -0800 (PST) Received: from mailman.zeta.org.au (mailman.zeta.org.au [203.26.10.16]) by mx1.FreeBSD.org (Postfix) with ESMTP id F004443EC2 for ; Tue, 31 Dec 2002 04:27:24 -0800 (PST) (envelope-from bde@zeta.org.au) Received: from katana.zip.com.au (katana.zip.com.au [61.8.7.246]) by mailman.zeta.org.au (8.9.3/8.8.7) with ESMTP id XAA31844; Tue, 31 Dec 2002 23:27:16 +1100 Date: Tue, 31 Dec 2002 23:29:21 +1100 (EST) From: Bruce Evans X-X-Sender: bde@gamplex.bde.org To: Andy Farkas Cc: freebsd-bugs@FreeBSD.ORG Subject: Re: bin/46633: Flase error report in swapon when adding too many disks In-Reply-To: <20021231110927.X35303-100000@hewey.af.speednet.com.au> Message-ID: <20021231232531.E51705-100000@gamplex.bde.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Tue, 31 Dec 2002, Andy Farkas wrote: > The error is not 'device busy', the error is 'out of swapdisk slots'. > > The first time this happened to me, I was stumped as to why it wouldn't > let me do it; the error message was not intuative at all. Man pages were > useless, there is no mention of swap device limits there. Only after From swapon.2: [EINVAL] The system has reached the boot-time limit on the num- ber of swap devices, vm.nswapdev. > It is not common knowledge that Freebsd has a limit to the number of swap > devices you can use. And it seems that this knowledge has been dropped > from -current: > > $ grep -i swap /sys/i386/conf/NOTES > $ i386/conf/NOTES only has the i386 parts. $ grep -i swap /sys/conf/NOTES # Allow this many swap-devices. # In order to manage swap, the system must reserve bitmap space that # scales with the largest mounted swap device multiplied by NSWAPDEV, # irregardless of whether other swap devices exist or not. So it options NSWAPDEV=5 # Disable swapping. This option removes all code which actually performs # swapping, so it's not possible to turn it back on at run-time. # This is sometimes usable for systems which don't have any swap space # (see also sysctls "vm.defer_swapspace_pageouts" and # "vm.disable_swapspace_pageouts") #options NO_SWAPPING $ Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message