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Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!news.rmit.EDU.AU!goanna.cs.rmit.edu.au!news.apana.org.au!cantor.edge.net.au!news.teragen.com.au!news.access.net.au!news.mel.connect.com.au!news.mel.aone.net.au!grumpy.fl.net.au!news.webspan.net!newsfeeds.sol.net!newspump.sol.net!howland.erols.net!cyclic.gsl.net!news.gsl.net!news-paris.gsl.net!news.gsl.net!news.kolumbus.fi!news.funet.fi!news.cs.hut.fi!news.clinet.fi!uunet!in3.uu.net!206.114.192.132!news.savvis.com!opus.anet-stl.com !zeus.anet-stl.com!not-for-mail From: doogie@zeus.anet-stl.com (Jason Young) Newsgroups: comp.unix.bsd.freebsd.misc Subject: FreeBSD and copy-on-write fork Date: 8 Mar 1997 01:09:49 GMT Organization: ANET-Internet Service Provider 1-800-776-8894 Lines: 28 Message-ID: <5fqe8u$9fh@opus.anet-stl.com> NNTP-Posting-Host: users.anet-stl.com X-Newsreader: TIN [UNIX 1.3 950824BETA PL0] Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:36746 Does FreeBSD have any sort of implementation of or plans for a copy-on-write fork such as the one Linux uses? I know when Linux implemented this, it was rather controversial and can result in a speed hit in some cases. However, I have a box here that runs a mud that regularly sits at around a 42MB process size. It forks itself at regular intervals to save a copy of the database to disk (once every half hour currently). The box has 80MB of RAM, and with the Linux copy-on-write fork, there is a HUGE win with respect to memory usage - currently savings of a good 32-33MB of RAM during this save. With normal fork, it would get driven pretty well into swap and drag down the responsiveness of the mud which is an important issue to us. Myself I don't see the big controversey. If it could be done in such a way that you could have both and choose - with a kernel recompile or some other way that the user could pick which suits their usage - then we all win. I'm no huge Linux fan, and I'm running FreeBSD 970209-SNAP on my work machine, home machine, and my quake server here at A-Net. I wouldn't mind getting FreeBSD on this mud machine also. Anything in progress in this arena? -- Jason Young A-Net Technical Staff