// run basic benchmark to estimate CPU clock frequency
void estimate_cpu_clock(void)
{
printf(" estimating cpu clock frequency...\n");
unsigned long int i, n = 1<<4;
struct rusage start, finish;
double extime;
do {
// trials
n <<= 1;
unsigned int x=0;
getrusage(RUSAGE_SELF, &start);
for (i=0; i<n; i++) {
// perform mindless task
x <<= 1;
x |= 1;
x &= 0xff;
x ^= 0xff;
}
getrusage(RUSAGE_SELF, &finish);
extime = calculate_execution_time(start, finish);
} while (extime < 0.5 && n < (1<<28));
// estimate cpu clock frequency
cpu_clock = 23.9 * n / extime;
printf(" performed %ld trials in %5.1f ms\n", n, extime * 1e3);
float clock_format = cpu_clock;
char clock_units = convert_units(&clock_format);
printf(" estimated clock speed: %7.3f %cHz\n", clock_format, clock_units);
}
int main() {
//
struct rusage t0;
struct rusage t1;
unsigned long int n;
double extime;
double cycles_per_trial;
unsigned int resolution = 256;
float rmse;
float maxe;
estimate_cpu_clock();
num_trials = (unsigned long int) ( cpu_clock / 1000 );
num_trials = num_trials < 256 ? 256 : num_trials;
unsigned int i;
// run benchmarks
for (i=0; i<NUM_BENCHMARKS; i++) {
// run precision test
benchmarks[i].precision_api(resolution,&rmse,&maxe);
// run speed test
n = num_trials;
benchmarks[i].benchmark_api(&t0,&t1,&n);
// compile results
extime = calculate_execution_time(t0,t1);
cycles_per_trial = extime * cpu_clock / (n);
// print results
printf(" %-20s : %10.6f s (%7.2f cycles/tr) : %10.8f rms, %10.8f max\n",
benchmarks[i].name,
extime,
cycles_per_trial,
rmse,
maxe);
}
printf("done.\n");
return 0;
}
int main() {
struct rusage start,finish;
unsigned long int num_trials = 1000000;
unsigned int n;
unsigned int D;
double extime;
double cpuclock=2.4e9;
double cycles_per_trial;
struct decim_crcf_opts opts;
for (D=2; D<=8; D*=2) {
printf("***** D = %u\n",D);
for (n=5; n<31; n+=4) {
opts.D = D;
opts.n = n;
benchmark_decim_crcf((void*)(&opts),&start,&finish,&num_trials);
extime = calculate_execution_time(start,finish);
cycles_per_trial = cpuclock * extime / (double)(num_trials);
printf("n : %3u, D : %3u, cycles/trial : %6.2f\n", n,D,cycles_per_trial);
}
}
printf("done.\n");
return 0;
}
