[net.micro.atari] unix DOES need an MMU

simon@mcvax.UUCP (Simon Kenyon) (01/02/86)

what about all the relocation fancy footwork that unix does
to handle the per process data area
what about multiple processes
are we proposing going back to the dark ages of rsx (unmapped)
where programs were linked for different load addresses
memory mangement is required for two reasons
protection and reloxcation
the first you can live without (that is if you never have pointers
which point nowhere)
the second is kind of hard to live without
--
simon kenyon
simon@mcvax.UUCP
national software centre, dublin, ireland

jimomura@lsuc.UUCP (Jim Omura) (01/05/86)

     I'm *really* getting tired of this discussion.  I have answer Mr.
Kenyon privately via 'mail' but this posting shows that it is likely he
has not been receiving my mail.  As such, I hope the Atari fans will
bear with me and we'll all hope he reads this:

In article <933@mcvax.UUCP> simon@mcvax.UUCP (Simon Kenyon) writes:
>
>what about all the relocation fancy footwork that unix does
>to handle the per process data area

     OS-9 does the same or similar 'fancy footwork' without an MMU

>what about multiple processes

     OS-9 handles multiple processes without an MMU

>are we proposing going back to the dark ages of rsx (unmapped)
>where programs were linked for different load addresses

     No.  If OS-9 can do it, then you can do it with some
other Unix or Unix clone.  Then again, why bother, you'll have
OS-9 anyway. :-)

>memory mangement is required for two reasons
>protection and reloxcation
>the first you can live without (that is if you never have pointers
>which point nowhere)
>the second is kind of hard to live without

     I can live without the protection.  I *have* been living without
it on my Color Computer, running OS-9 (6809) for some time now.  I
think most Atari 520ST users will find it quite satisfactory.  Please
go look at OS-9 68K before you do any further posting.  I read
net.micro.atari to read about Atari.

>--
>simon kenyon
>simon@mcvax.UUCP
>national software centre, dublin, ireland


-- 
James Omura, Barrister & Solicitor, Toronto
ihnp4!utzoo!lsuc!jimomura
Byte Information eXchange: jimomura
(416) 652-3880

wdm@ecn-pc.UUCP (Tex) (01/08/86)

In article <933@mcvax.UUCP> simon@mcvax.UUCP (Simon Kenyon) writes:
>
>what about all the relocation fancy footwork that unix does
>to handle the per process data area
    < Lots more "reasons" that UNIX needs an MMU >
>simon kenyon

    Your right, UNIX DOES need an MMU.  I'll call Microsoft and H-P immediately
    and tell them to stop selling Xenix and HPUX because they can't possibly 
    work.  Boy are they going to be pissed.  Oh well, they should have asked
    if they needed an MMU before they went ahead and ported UNIX to hardware
    that doesn't contain an MMU.

    Bill Michael