Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.csd.uwm.edu!lll-winken!arisia!sgi!shinobu!odin!rock!mitch
From: mitch@rock.sgi.com (Thomas P. Mitchell)
Newsgroups: comp.sys.sgi
Subject: Re: Power Series Arch Description Request
Summary: some background reading
Keywords: Cache, Locks, Scheduling, Threads
Message-ID: <473@odin.SGI.COM>
Date: 7 Sep 89 21:31:12 GMT
References: <89Sep6.182533edt.4956@jarvis.csri.toronto.edu>
Sender: news@odin.SGI.COM
Organization: Silicon Graphics Computer Systems,  Mountain View CA.
Lines: 52

In article <89Sep6.182533edt.4956@jarvis.csri.toronto.edu> dret@DGP.TORONTO.EDU (George Drettakis) writes:
>I am interested in getting my hands on a document that will describe
>the Power Series parallel architecture. 

Here are some pointers:

1)   "UNIX Papers for UNIX Developers and Power Users" see:
Article 14 Multiprocessor UNIX by Tom Jermoluk (Tom is here
at SGI.) Edited by Mitchell Waite Howard W. Sams and
Company ISBN  0-672-22578-6

2)   Wagner, J.C., and Barton, J.M., "Threads in System V:
Letting UNIX parallel Process", a work-in-progress paper
presented in ;login:, USENIX Association, Vol. 12, No. 5,
September/October 1987.

3)   Beck, Bob, and Olien, Dave, "A Parallel Programming
Process model", in USENIX Conference Procedings, Winter,
1987.

4)   Barton, J.M., Wagner, J.C. "Beyond Threads: Resource
Sharing in UNIX," USENIX Procedings, 1987.

5)   Dijkstra, E.W. "Cooperating Sequential Processes,"
Technical Report EWD-123, Technological University,
Eindhoven, The Netherlands, 1965.

6)   Gerry Kane. "mips RISC Architecture"
Prentice Hall, Englewood Cliffs, N.J.  ISBN 0-13-584293-X

Keys to understanding are: 

There is one run queue.

Parallel regions in code are managed as seperate
processes.  All the rules of shared memory problems apply.
It is the responsibility of the programmer (in 'c') to
understand any data dependancies.   The pfa (Power FORTRAN
Accelerator) identifies regions at the do loop level which
may safely be run in parallel for the FORTRAN compiler. Yea
the programmer may know of other regions. Worse yet, he may
think he does.

The user may need to discover (profile) if the overhead of
spawning the sub-processes and resyncronizing is greater
than the work done in the loop.

Unix needs a good spelling checker (from vi).

 
Thomas P. Mitchell (ARPA:mitch@csd.sgi.com, UUCP:  {decwrl,ucbvax}!sgi!mitch )
Rainbows -- The best (well second best) reason for windows.