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Path: sserve!newshost.anu.edu.au!munnari.oz.au!news.Hawaii.Edu!ames!agate!howland.reston.ans.net!vixen.cso.uiuc.edu!isr0004.urh.uiuc.edu!rich From: rich@isr0004.urh.uiuc.edu (Rich) Newsgroups: comp.os.386bsd.questions Subject: Re: Disk Thrashing question Date: 28 Sep 93 07:13:58 GMT Organization: University of Illinois at Urbana Lines: 76 Message-ID: <rich.749200452@isr0004.urh.uiuc.edu> References: <1993Sep27.170443.444@doug.cae.wisc.edu> <2884k2$d9k@pdq.coe.montana.edu> NNTP-Posting-Host: isr0004.urh.uiuc.edu nate@bsd.coe.montana.edu (Nate Williams) writes: >In article <1993Sep27.170443.444@doug.cae.wisc.edu>, >John Edward Tillema <tillemaj@cae.wisc.edu> wrote: >> >> >> I have had FreeBSD running for about a month or so on my 486 >>now, and have noticed one major disadvantage to it compared to Linux >>(at least for me). It seems to take virtually nothing to cause me >>to start swapping like crazy, and even hang the system. My setup is: >>8 Meg Ram, 17 Meg swap space, 486/33, 340 Meg drive, with 300 for Unix. > ^^^^^^^^^ >>If i run anything in the background, or compile one program, or sun >>a comm program, you can hear the disk swapping like crazy and performance >>really drops(you can easily type a line of text before the first character >>is printed). I can even hang the system. I found a good way of doing >>this is the following: >> run olvwm. >> run XV and view a gif (or jpg, or probably anything), not necessarily >> large, the last one was only 200k. >> run emacs and load in a large file, here I'm talking about a 7 meg file. >With X running (2 - 3 MB), and xv (probably 1 MB with the image displayed) >the system (2 MB in memory) AND emacs ( 1 MB for emacs + 7 MB for the >file you're editing ) you've used up more space than you have available. I have 8 meg too and I have noticed the same problem... NetBSD hung when i tried to compile xv. And i was not even in X at the time. I had two users with screen running. That's ridiculous, When i compiled xv on linux i had other users logged in and the system only slowed to mildly irritating while it crashed under NetBSD. And what does only having 8 meg real ram have to do with it? That is why we have swap, that is what it is there for. If bsd cant handle 14 or so megs being eaten, 6 in swap then it's not a very efficient kernel. I could thrash linux to my hearts content, (XF86_SVGA, two or three xterms, a load or two a couple remote clients, even an Xfilemanager) and i never got such poor performance. Is this because of the static binaries? i sure hope so, because if not the BSD people could learn a lesson or two from linux. >Now, since emacs brings everything into memory, there is nothing you can >do about using up all your memory, and Linux *should* act the exact same >way since emacs == emacs == emacs when it comes to GNU emacs. I dont use emacs cant tell you.. >Basically, you've got processes competing for available memory space, most >notably emacs. >I am mildly suprised that Linux handles running out of memory better, >especially after hearing some of the horror stories that happen when >Linux runs out of memory. I suppose it's possible that you are also >running out of swap space. A way to check that is to run swapinfo in >another xterm when you start up emacs, and see what state your system is >in. Horror stories? I dont think it is considered a horror story when your machine decides to reboot when it is out of memory.. at least it's over in a minute or two and you can get on with your work, rather than a hang which you have to leave there for a while to see if it is going to recover. >Nate >-- >nate@bsd.coe.montana.edu | Freely available *nix clones benefit everyone, >nate@cs.montana.edu | so let's not compete with each other, let's >work #: (406) 994-4836 | compete with folks who try to tie us down to >home #: (406) 586-0579 | proprietary O.S.'s (Microsloth) - Me --------------------------------------------------------------------------- Richard A. Nuttle Internet: Richnut@uiuc.edu "I'll do it tomorrow...." NeXT: ran59961@sumter.cso.uiuc.edu "or maybe the next day.." Bitnet: FREE3277@UIUCVMD ---------------------------------------------------------------------------