Subject: Re: CCL:Macintosh questions

From: Simon Berneche <[email-masked]>
Date: Thu, 17 Oct 2002 14:09:22 -0400

Joe,

> 1) What is the large-scale/floating point performance between the 
> newest
> Macs and Intel machines?  Is there any particular compilers and/or 
> switches
> needed to realize max performance?

The G4 processor is not in a position to compete with Intel/AMD cpu for 
number crunching except if you can limit your calculation to single 
precision floating points. In that case you can use the G4's vectorial 
unit (Altivec) to bring the performance at the level of what Intel/AMD 
cpu would provide.

> 2) How does OSX compare to Linux as a development environment?  Can one
> do C and Fortran coding (or more-modern languages) on these machines?
> Are there particular problem areas?

The same tools are available on both platforms. You can install all gnu 
stuff, including the X11 window server (and run simultaneously X11 and 
Apple's Aqua windowing systems). Apple's compiler is in fact gcc (they 
don't ship g77 with it, but it can easily be installed).  If you do a 
lot of Fortran I would recommend buying one of the commercial compilers 
(Absoft has a good one).  Python and perl are pre-installed, I think 
Ruby is also. Even if you don't need to use it, a lot of people seem to 
appreciate the Cocoa API and the Obj-C language (both are heritages of 
NextStep, the ancestor of MacOS X).

> 3) Is there any problem giving presentations from a Mac rather than
> a PC (both laptops)?  Or, are the suitable video-out ports supported
> on each?

No problem at that level. Also, there is no chance that your slideshow 
application would bring the OS down in middle of a presentation. The 
app might crash, but it has a really low-low probability of affecting 
the OS, like it could have been the case with MacOS 9 or Windows.

In two words, with MacOS X underneath, Macs are really good 
desktop/laptop UNIX machines with the bonus that you can also run 
mainstream applications like Photoshop and Office without rebooting in 
an other OS (Windows or MacOS 9) or switching to another machine.  They 
are not that great for number crunching, but that could change rapidly 
in the coming year with the latest announcement of IBM PowerPC 970 chip.

Hope this helps.
Simon

____________________________________________

Simon BERNECHE
B.R. Theoretical Biophysics Laboratory
Weill Medical College of Cornell University

email: [email-masked]
tel:(212)746-4237
fax: (212)746-4843
____________________________________________

---

From: Richard Gillilan <[email-masked]>
Date: Thu, 17 Oct 2002 14:36:56 -0400

Joe M Leonard wrote:

Joe: I use RH Linux at work running on a 1GHz AMD but use
     MacOS X (Jaguar) at home on an older 400Mhz G4. When 
     I upgrade my box at work I will choose Mac. Not so much 
     because G4's are faster, but because the system is so nice
     to work with and finally has all the tools I need. 

> I would welcome any guidance on the following questions (and
> assume somebody reading this has played with new Macintoshes):
> 
> 1) What is the large-scale/floating point performance between the newest
> Macs and Intel machines?  Is there any particular compilers and/or switches

I have not run any serious benchmarks. I'll do a quicky tonight just out 
of curiosity.  Disk access seems to be quite a bit faster than the IDE
disk I'm currently using under Linux. The default compiler is gcc. I did 
skim though the compiler manual ... there are examples and the syntax is 
pretty simple. You need to recode loops to take advantage of the pipeline. 
At the present time, I don't consider it worth optimizing code since I 
don't run many production jobs at
home. We are still building another large diskless Linux cluster for production
work here at MacCHESS. Cost is the main consideration there. You can run MPI
accross multiple G4's of course. Michael Love in our group does a lot of that.

> Are there particular problem areas?

Apple has a very very nice development environment ... all comes free with 
Jaguar (even a version of Python is installed by default). Just double 
click on a source code file and it will launch the Project Builder
(http://developer.apple.com/tools/projectbuilder/). I use it mainly
as an editor, but it is something like Dev Studio in the M$ world only for
gnu compilers. I wish they had a Linux version for work.

Yes you can get FORTRAN (at least g77, probably others by now). 
Essentially all Linux/Unix apps have been ported. You can check
out www.gnu-darwin.org or http://fink.sourceforge.net/ to 
see what all is available.

With XDarwin, you can run X-windows apps on your Jaguar desktop,
(I run OpenDX, gnuplot and xv this way). 
   or simply run Darwin with XFree86 and have the box look just like anyother
   Linux or BSD.

> a PC (both laptops)?  Or, are the suitable video-out ports supported

As far as I know (I don't own a laptop). I use PowerPoint for the Mac
and just burn a CD that will run work on either type machine.

Richard

> 
> Thanks in advance!
> 
> Joe Leonard
> [email-masked]
> 
> P.S. I figure our audience is sufficiently different to make "typical reviews"
> less than valuable :-).
> 
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