C: using clock() to measure time in multi-threaded programs
- by Shinka
I've always used clock() to measure how much time my application took from start to finish, as;
int main(int argc, char *argv[]) {
const clock_t START = clock();
// ...
const double T_ELAPSED = (double)(clock() - START) / CLOCKS_PER_SEC;
}
Since I've started using POSIX threads this seem to fail. It looks like clock() increases N times faster with N threads. As I don't know how many threads are going to be running simultaneously, this approach fails. So how can I measure how much time has passed ?
