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From: gerst@ecs.umass.edu
Newsgroups: comp.sys.next
Subject: RE: YASOQ
Message-ID: <11694.275cf7f6@ecs.umass.edu>
Date: 5 Dec 90 13:36:37 GMT
Lines: 53

Reply-To: lloyd@ucs.umass.edu

>Subject: Re: YASOQ
>From: bennett@mp.cs.niu.edu (Scott Bennett)

>In article <1990Dec4.032737.12258@engin.umich.edu> gilgalad@caen.engin.umich.edu (Ralph Seguin) writes:
>> [questions about swap files and multiple HD's etc.. deleted]

>     The so-called "accelerator" disk on the 68030 cubes is apparently ..
>[some conjecture about the 40 meg HD deleted]

   so-called? well, try paging on the OD, MISERABLE (loud too!). Anyways,
what you want to do it look at '/etc/rc','/etc/rc.swap' and do a man on
'mach_swapon', I just recently reconfigured my system so the 40 meg HD
is swapspace and accounts.  I'm a single user system, and this is just dandy.

   /etc/rc - the boot script, it executes /etc/rc.swap and mach_swapon.

   /etc/rc.swap - a shell script that "figures out" if the 40 meg swap
    disk is present, mounts it, sets up a swapping file and /tmp.

   mach_swapon - used for setting up a swapfile, look at the man pages,
     I'm not going to repeat them here. It allows you to specify hi/low
     water marks and whether it is a preferred swapfile or not.

Look at the above, if you have a weak stomach for modifying boot scripts,
I'd get someone else to be responsible for editing anything :->

a lot of information in rc.swap is "hardcoded" in, expect to do a lot
of fiddling.

As for memory, swapfile and other setup recommendations, I would take a
good look at how much resources you typically use.  It's kinda hard to
make recommendations based on your name. Being a single user non-networked
node is quite different from being a server that runs mega lisp progs.

Now, I have a question.  mach_swapon is documented as supporting 
multiple swapfiles.  In my experience, this is NOT the case.  I have
configured 1, 2 and 3 swapfiles in various combinations across the OD
and HD. when #1 preferred swapfile hits the high water mark, the system
comes to a grinding halt.  I spent a solid day reconfiguring swapfiles 
and rebooting (reboots and fsck are fun!).  And the system never touched
any of the secondary swapfiles.

Has, does or will mach_swapon *USE* more than one swapfile?

>>PS- Somebody mentioned /etc/swaptab for swapping space info.

 uh huh. falls under 'mach_swapon'.

'Digital Librarian' is your friend. ('man' too!)

Chris Lloyd - lloyd@ucs.umass.edu