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Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!news.mira.net.au!pumpkin.pangea.ca!www.nntp.primenet.com!nntp.primenet.com!news.mathworks.com!news.maxwell.syr.edu!news-was.dfn.de!news-kar1.dfn.de!news-stu1.dfn.de!news-mue1.dfn.de!news-nue1.dfn.de!news-lei1.dfn.de!news-ber1.dfn.de!zrz.TU-Berlin.DE!IN-Berlin.DE!fub!mind.de!nostromo.in-berlin.de!ripley From: ripley@nostromo.in-berlin.de (H. Eckert) Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: How to increase size of vn-device swapfile? Date: 21 Apr 1997 20:28:07 GMT Organization: Private access site (FreeBSD 2.2.1), Berlin, Germany, Europe Lines: 45 Message-ID: <slrn5lnjen.qoo.ripley@nortobor.nostromo.in-berlin.de> References: <5jf770$mbj@chenab.lums.edu.pk> NNTP-Posting-Host: nortobor.nostromo.in-berlin.de Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Newsreader: slrn (0.9.3.2 UNIX) Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:39607 aslam@lums.edu.pk (Sohail Aslam): > 3. put into /etc/rc.local the line > vnconfig -ce /dev/vn0c /var/swap0 swap > > 1. How can increase the size of /var/swap0 (the file)? Simply boot into single-user mode so the file isn't in use as a swap-area. > 2. How can I disable swapping to the vn-device? You can't when it has been attached. This is a design limitation that presumably can't be removed easily. To fix this it would be necessary to designate a swap-area as "dying" so that nothing will be stored to it anymore. Every time a page is read from a dying swap-area it should be transferred to a living one and eventually nothing is stored in the dying area, so it can be marked dead. Only a truly dead area could be detached at all. Another approach would be to kill all processes that have some pages in a dying area (not really a good idea) or actively transferring the pages to a living area (possibly freezing the whole machine in the meantime). Anyway, a solution would be quite complicated and would need severe changes on the heart of the system... > 3. Is the performance of swapping/paging on a vn-device the same as on > a hard partition? AFAIK direct swapping is more efficient since it doesn't have to go through the filesystem. > For the time being, I created another vn-device (vn1c) and another 64MB > file in /var (swap1) and vnconfig'd swap on it. Unless you reboot the machine there isn't another way to do it. Dynamically appending NULs to the active swap-file is something I'd avoid, too. I don't think the system would like it. Greetings, Ripley -- H. Eckert, 10777 Berlin, Germany ISO 8859-1: Ä=Ae, Ö=Oe, Ü=Ue, ä=ae, ö=oe, ü=ue, ß=sz. "(Technobabbel)" (Jetrel) - "Müssen wir uns diesen Schwachsinn wirklich anhören?" (Neelix)