Timing program processes

[theDot]

Working on a programming project, and I was just wondering if anyone knew of any (preferably Windows) programs or methods to time execution/process time.

I'm just trying to compare some various methods and see what the fastest is (and it's stuff I can't really use big-O analysis for, since it's things like opening textfiles, database searches, where I have limited control over the actual process my application is calling).

 

[Darth Bagel]

im guessing the language is java, from your terminology?

 

[theDot]

C++

...

 

[Darth Bagel]

use a pair of clock_t's:

clock_t start, end;

start = clock();
// do stuff
end = clock();

printf("time: %lf msec.\n", (double)(end-start) / (double)CLOCKS_PER_SEC * 1000.0);

 

[theDot]

Interesting, thanks.

Can these be verified as accurate?

 

[Darth Bagel]

theyre accurate enough, especially if youre using them to compare different implementations, because you can use the same format. in an absolute sense, i dont really know. theyre listed in the gnu c library, among quite a few other places, so they cant be that inaccurate.

 

[AMDmachine]

I am no C++ guru, but I've found this link: http://technology.chtsai.org/w98timer/

....he two Win32 API functions performed better than the run-time library functions, but only one of them reached near-millisecond resolution. It was concluded that only the Multimedia Timer is qualified to be used in psychological experiments.