why C clock() returns 0
- by eddy ed
I've got something like this:
clock_t start, end;
start=clock();
something_else();
end=clock();
printf("\nClock cycles are: %d - %d\n",start,end);
and I always get as an output "Clock cycles are: 0 - 0"
Any idea why this happens?
(Just to give little detail, the something_else() function performs a left-to-right exponentiation using montgomery represantation, moreover I don't know for certain that the something_else() function does indeed take some not negligible time.)
This is on Linux. The result of uname -a is:
Linux snowy.*****.ac.uk 2.6.32-71.el6.x86_64 #1 SMP Fri May 20 03:51:51 BST 2011 x86_64 x86_64 x86_64 GNU/Linux
