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From: ralphw@ius3.ius.cs.cmu.edu (Ralph Hyre)
Newsgroups: comp.sys.next
Subject: Mach features? (Re: Paging and swapping to a removable disk?)
Message-ID: <3352@pt.cs.cmu.edu>
Date: 20 Oct 88 01:48:59 GMT
References: <12670001@eecs.nwu.edu> <3924@encore.UUCP>
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In article <3924@encore.UUCP> bzs@xenna (Barry Shein) writes:
>>Does Mach (on a NeXT, at any rate) do memory swapping to disk?
>>If so, what does it use for the swap area at times when the laser disk is out?
>I'll stick my neck out and say that I don't believe that you'll be
>able to remove the optical disk if that's what you're paging and
>swapping to 

That would be my guess, but CMU-CS flavored Mach kernels (supported by
our excellent facilities staff here) have a nifty resource-pausing feature
that will block selected processes that can't get at needed resources
(like, free disk blocks when the disk is full).  This has been in CMU-CS
kernels since the BSD 4.1 days, I believe.  It might be tough to extend
this to paging and swapping, but if anyone can do it, NeXT can.

I don't know if that what set of sources NeXT started with, though.

disclaimer: I am no authority on how CMU and NeXT interact.
-- 
					- Ralph W. Hyre, Jr.
Internet: ralphw@ius3.cs.cmu.edu    Phone:(412) CMU-BUGS
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"You can do what you want with my computer, but leave me alone!8-)"