GNAT and symmetric multi-processing!

GNAT and symmetric multi-processing!

[Chris Morgan]

Dear all,

-- a preamble
  Now that tasking works in GNAT on Sun/SPARC/Solaris2.3, I am trying
to awaken interest in the real-time possibilities of Ada95 by
sponsoring a little programming competition within my company. Of
course knowledge is its own reward, but knowing the preferences of my
colleagues who share my interest in GNAT/Ada95, the reward is some
amount of alcoholic refreshment calibrated to the winners needs, so as
you can see I am risking financial ruin for the sake of promoting
Ada95!
  Briefly, I have challenged my colleagues to write an Ada95 program
that demonstrates good use of tasking to perform some array of
calculations, for example plotting the famous Mandelbrot set. Some
dynamic creation of tasks is envisaged, possibly with the program
running repeatedly to ascertain the optimum number of tasks. Maybe
asynchronous transfer of control would also come in handy to exit
points on the set which can't decide which pole to go to in a sensible
amount of time...

--a question
  Does anyone know whether the tasking provided by POSIX threads in
GNAT will take advantage of a multi-processor machine such as a 4-cpu
SPARCstation2000? This activity is strictly extra-curricular, so I have
not completed reading all the GNAT info, but my understanding so far
doesn't include any feel for whether an implementation must offer SMP,
even though it clearly has the opportunity given a POSIX foundation.

--a request
  One feature that would spice up the above project is the ability to
display the results graphically. Does anyone have a short program which
interfaces to X-Windows that they have compiled under GNAT on Solaris
(or similar) which they could share with us? I think there is a need
for a very simple X-based graphics library in the GNAT examples
directory, as even with X bindings, there is still the difficulty that
X is very large and intimidating. If I don't get any replies, I will
attempt something myself and then (eventually) post the results, but I
wouldn't hold your breath :-)
------------------------------------------------------------------------

--
-- Chris Morgan
-- SMCS Project, BAeSma Ltd, Scientific House, 40-44 Coombe Rd,New
Malden
-- Surrey, England, UK
-- E-mail: chris.morgan@baesema.co.uk
-- Currently grappling with Ada95 via GNAT2.03 on Sun-SPARC-SOLARIS2.3
-- Member, Team Ada
------------------------------------------------------------------------

Re: GNAT and symmetric multi-processing!

[John Howard]

Chris Morgan (chris.morgan@baesema.co.uk) wrote:
: Dear all,
: -- a preamble
:   Now that tasking works in GNAT on Sun/SPARC/Solaris2.3, I am trying
: to awaken interest in the real-time possibilities of Ada95 by
: sponsoring a little programming competition within my company. Of
[deleted]
:   Briefly, I have challenged my colleagues to write an Ada95 program
: that demonstrates good use of tasking to perform some array of
: calculations, for example plotting the famous Mandelbrot set. Some
: dynamic creation of tasks is envisaged, possibly with the program
: running repeatedly to ascertain the optimum number of tasks. Maybe
: asynchronous transfer of control would also come in handy to exit
: points on the set which can't decide which pole to go to in a sensible
: amount of time...
[deleted]
: --a request
:   One feature that would spice up the above project is the ability to
: display the results graphically. Does anyone have a short program which
: interfaces to X-Windows that they have compiled under GNAT on Solaris
: (or similar) which they could share with us? I think there is a need
[deleted]
: -- Chris Morgan
: -- Member, Team Ada

Take a look at the Robot Auto Racing Simulation (RARS) competition and 
mailing list.  It has recently started out in C code and the Borland Graphic 
Interface (BGI) but it is actively being ported to other environments.

There are at least two people working on an Ada 95 implementation.  My 
version is for OS/2 and eventually an OpenGL interface.  The Presentation 
Manager graphics interface will be used initially.  RARS is a neat idea 
and a good way for me to better learn Ada 95, OS/2, and OpenGL 
programming while sticking with one project.  I believe that OS/2 performs 
symmetric multi-processing (SMP).

To get on the RARS mailing list:
Send a message body of:
  subscribe rars-list
to: listserv@NETCOM.COM
with a blank subject.

There is a new tutorial accessable to members on the mailing-list.

The RARS executables, source code and documentation is at 
magdanoz.mcafee.com:/bin/ftp/rars

Currently, everything is written in C.  One guy is using Ada 95 to 
interface to the C code.  I am writing an Ada 95 version only.

The simulator is being rewritten to accept cars defined as dynamic link 
libraries (DLL).  The outcome of a race will be sent to a text file.  My 
version will also output a 3d vector for each car during a discrete time 
frame for the race.  Each car will have its own output data file.  A generic 
viewer program can then interpret the 3d vectors and recreate the race 
for display.

Also, discussion occurs in a new newsgroup called something like 
comp.games.ai or similar.  I don't remember the exact group name.

The first RARS competition is April 29 but my version will not be ready by 
then.

--John Howard--Team Ada--Team OS/2

Re: GNAT and symmetric multi-processing!

[Tore Joergensen]

John Howard (jhoward@solar.sky.net) wrote:
: [deleted]  I believe that OS/2 performs 
: symmetric multi-processing (SMP).

There is a version of OS/2 that does SMP, but I don't know if it will
distribute threads (ie. ada-tasks) or only processes. The rationale
(III.3.7) mention dividing programs in to partitions. "Partitions
are intended to support distributed processing,...". I guess partitioning
is overkill for SMP :-) If the operating system doesn't SMPs the tasks,
then you could use OS-calls to make processes (but that isn't portable). 
______________________________________________________________________
Tore B. Joergensen,    |    e-mail:     tore@lis.pitt.edu
a norwegian student    |    snail-mail: 2201 Pittockstr.
a long way from home.  |                Pittsburgh, 15217 PA
                       |    web:        http://www.pitt.edu/~tojst1

Re: GNAT and symmetric multi-processing!

[Dale Pontius]

In article <3lpto7$9ra@toads.pgh.pa.us>, tore@lis.pitt.edu (Tore Joergensen) writes:
> John Howard (jhoward@solar.sky.net) wrote:
> : [deleted]  I believe that OS/2 performs
> : symmetric multi-processing (SMP).
>
> There is a version of OS/2 that does SMP, but I don't know if it will
> distribute threads (ie. ada-tasks) or only processes. The rationale
> (III.3.7) mention dividing programs in to partitions. "Partitions
> are intended to support distributed processing,...". I guess partitioning
> is overkill for SMP :-) If the operating system doesn't SMPs the tasks,
> then you could use OS-calls to make processes (but that isn't portable).

I believe I remember hearing that SMP OS/2 can distribute threads
among processors.

Dale Pontius
(NOT speaking for IBM)