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From: miller@CS.ROCHESTER.EDU (Brad Miller)
Newsgroups: comp.sys.mac
Subject: Re: Protected mamory (SIC)
Message-ID: <1989May19.171943.6503@cs.rochester.edu>
Date: 19 May 89 21:19:43 GMT
Organization: U of Rochester, CS Dept, Rochester, NY
Lines: 30


    Date: 19 May 89 12:45:43 GMT
    From: ts@cup.portal.com (Tim W Smith)


    A single large address space makes IPC easier? Yuck!

    IPC should look like network communications.  Then you can
    make your IPC code also work across different machines
    transparently.

There are two basic models for IPC: shared memory and message passing. There
are advantages and disadvantages to both. Shared memory (remote memory
reference) can indeed work across different machines transparently if you
are clever. 

For further information on IPC, and various kinds of memory protection
issues, I suggest you peruse:

_Operating Systems -- An Advanced Course_ Bayer, R. et.al eds.

Springer-Verlag 1979

More interesting issues in terms of parallel architectures and the shared
memory vs. message passing tradoffs can be found in 

"Psyche: A General-Purpose Operating System for Shared-Memory
Multiprocessors" by Scott and LeBlanc, TR 233, August 1987 University of
Rochester Computer Science Dept. ($1.25 - mail $ & request to TR Secretary,
Computer Science Department, University of Rochester, Rochester, NY 14627)