Re: CPU timer - Gpc

2 Mar 2004


      ...
On Mon, 1 Mar 2004, Toby Ewing wrote:
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Hi, all
Frank suggested using the CPU timer, and I agree that it's a much better
benchmark than the clock timer (I keep discovering gems in gpc.pas!).  But I'm
getting identical results from the two timers:
var
   time1, time2 : longCard;
   dummy,
   cpu1, cpu2   : integer;
..
   time1 := GetMicroSecondTime;
   dummy := 0;
   cpu1 := GetCPUTime(dummy);
for i := 1 to big do j := randNorm(0.0, 1.0);
dummy := 0;
   cpu2 := GetCPUTime(dummy);
   time2 := GetMicroSecondTime;
   writeln('Time for ', big:1, ' randNorms: ', ((time2-time1)*0.000001):7:2,
      ' seconds, ', (cpu2-cpu1):5, ' cpu seconds.');
..
When the computer is idle except for this program, I get:
Time for 100000000 randNorms: 171.03 seconds, 171 cpu seconds.
Why not try a program that does user input, say through a readln.
When testing, you can delay the input as long as you wish.  The
net cpu time should be minimal, but the wall clock time obviously
increases as you wait.
Tom