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Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.cs.su.oz.au!metro!metro!munnari.OZ.AU!spool.mu.edu!usenet.eel.ufl.edu!bofh.dot!arclight.uoregon.edu!news.dacom.co.kr!news.kreonet.re.kr!bofh.dot!usenet.kornet.nm.kr!agate!howland.reston.ans.net!vixen.cso.uiuc.edu!newsfeed.internetmci.com!in1.uu.net!newsreader.sprintlink.net!helena.MT.net!nate From: nate@trout.sri.MT.net (Nate Williams) Newsgroups: comp.unix.bsd.misc Subject: Re: Why does this program panic 4.4BSD? Date: 25 May 1996 20:05:16 GMT Organization: SRI Intl. - Montana Operations Lines: 37 Message-ID: <4o7p5s$kh0@helena.MT.net> References: <4o2kn3$21u@panix2.panix.com> Reply-To: "Nate Williams" <nate@sneezy.sri.com> NNTP-Posting-Host: trout.sri.mt.net [ Courtesty email send to author as well ] In article <4o2kn3$21u@panix2.panix.com>, Thor Lancelot Simon <tls@rek.tjls.com> wrote: >I've been playing around for ways to generate some baseline load on the VM >system as part of a benchmark I'm writing to approximate the application we >develop where I work. > >The following code appears to quite reliably panic every 4.4 derivative I've >run it on, when run by an ordinary, unprivileged user. In fact, I suspect >that it rather irritated the folks who run the BSDi machine I occasionally >use... I was rather surprised that it caused such lossage there, too. You obviously didn't try it on FreeBSD. I'm runing on older version of 2.1-stable (a couple minor patches from 2.1, which I don't think are VM related). I just ran it with MEGS=4, and then for giggles MEGS=64 and it's just sitting in memory with 64MB malloc'd doing nothing other than locking/unlocking memory over and over again. I also used mmap and nothing seemed to change, so mmap()'ing the data in works as well. >Yes, I know that it never unlocks the 0-1MB range of the allocation. That's >a bug. :-) But still, holding that 1MB in core shouldn't cause utter, >near-instantaneous lossage, should it? The VM system is *completely* different than all of the other 4.4BSD derivatives, so what you are seeing is probably generic to any of the systems using the 4.4BSD VM design. Nate -- nate@sri.com | Research Engineer, SRI Intl. - Montana Operations nate@trout.mt.sri.com | Loving life in God's country, the great state of work #: (406) 449-7662 | Montana. home #: (406) 443-7063 | A fly pole and a 4x4 Chevy truck = Heaven on Earth