Mac Forum / Country Specific / Australian Mac Group / September 2004

so?...he just wants to test the cpu.

Good suggestion, I'm not a unix head though :(  What exactly would I type in
the terminal to make this happen?
Thanks :)

On 2/9/04 1:41 PM, in article ch64od$124$1@enyo.uwa.edu.au, "Chris McDonald"
<chris@csse.uwa.edu.au> wrote:

Since you are dealing with 'clients' (and I presume charging them)
perhaps a testing app like Tech Tool Pro would be a good investment - it
tests lots of things, and you can charge for a comprehensive testing session

David

C doesn't seem to like calculating more digits.... It's a combination of my
code, and the limitation of the variables in C....

You can however make the code repeat several times with a simple loop:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

int main();
double createPi(long);

int main()
{
long double pi;
for(x=0; x<100 ;x++)
{
   pi = createPi(1000);
}
   printf("\n\n%lf\n", pi);

   printf("Processing time: %lf\n", (long double) (clock()/(long
double)CLOCKS_PER_SEC));

exit(0);
}

double createPi(long numtimes)
{
   long double numerator = 4.0;
   long double sum = 0;
   long double denominator;
   numtimes = 1000000000;

   for(denominator = 3; denominator <= ((numtimes * 2) + 1); denominator +=
4)
   {
       sum += (numerator / denominator);

       sum -= (numerator / (denominator + 2));
   }
   sum = 4 - sum;

   return sum;
}

The number 100 in:
for(x=0; x<100 ;x++)
Tells it how many times to repeat the calculation. Using this, you can
perhaps run the original code once and see how long it takes... Then
calculate how many times you would need to run the code in order to make it
run overnight.... eg. it take 74 seconds to run on my machine, so:
400 would make it run for about 8-9 hours... ON MY MACHINE.... It ill be
different for you....

This app. runs the same as the last one....

The important thing here, is this is only processing maths. If you are
trying to detect CPU related errors, it may not pick them up....
The CPU is a complex thing. Calculating Pi will only use certain parts of
the CPU - most likely the FPU in fact.... And any math related
components.... But some parts of the CPU instruction set relate only to for
example, multimedia, or audio processing etc... Which means these parts of
the CPU will be pretty much unused while my program is running.... So it's
not necessarily the best test.... I think a thorough benchmarking
application would do a much better job, since they generally test many
aspects of PC performance....

- David Angelovich

There are freeware programs that calculate pi to any number of digits
required. This could load the processor nicely overnight.

I forgot... You need to install the Developer Tools...
It's either on a CD that came with OS X, or can be installed from
Applications: Installers: Developer Tools: Developer.mpkg if OS X came with
your Mac....

- David Angelovich

Thanks for the dope on Techtool - one more suggestion, what about a
small app written in basic - eg a=a=1 etc in a loop.  Should n't be too
hard to write and basics these days allow free standing apps to be made

David - who likes to think up ideas - some work - some don't - but the
challenge is good