On Wed, 8 Jun 2005, Matthew Miller wrote:
On Wed, Jun 08, 2005 at 06:40:34AM -0700, Globe Trotter wrote:utilization. Unless I misunderstood the documentation, clock() provides the processor time and so the difference between clock() at the beginning of the call to an algorithm and the end would provide me with the CPU time elapsed. However, if for some reason the processor was running at 75% or whatever, my reported time would be affected, and hence there would not really be a fair comparison. Does anyone have any ideas/suggestions as to how I may settle this issue?
clock() returns an approximation of the CPU time used by the actual process, so while load from other programs is a factor (particularly since it'll make your program wait for IO, etc.) it should do basically what you want.
Also check out the times(2) facility. It's not ISO C, but it is POSIX and it has some advantages over clock(3).
-- Matthew Saltzman
Clemson University Math Sciences mjs AT clemson DOT edu http://www.math.clemson.edu/~mjs
