void CPUBenchmark::systemCallOverhead(fstream &file) {
cout << "3. System call overhead starts:" << endl;
double overhead;
double sum = 0;
cout << "3.1 Get non-cached system call overhead overhead: ";
file.open(SYSTEM_CALL_OVERHEAD_FILE, ios::out);
if(file.is_open()) {
for(int i = 0; i < OP_TIMES; i++) {
overhead = getSystemCallOverhead(false);
file << overhead << "\n";
sum += overhead;
}
cout << (sum / OP_TIMES) << " cycles" << endl;
file.close();
}
else {
cout << "Can't open file-" << SYSTEM_CALL_OVERHEAD_FILE << endl;
}
sum = 0;
cout << "3.2 Get cached system call overhead overhead: ";
file.open(CACHED_SYSTEM_CALL_OVERHEAD_FILE, ios::out);
if(file.is_open()) {
for(int i = 0; i < OP_TIMES; i++) {
overhead = getSystemCallOverhead(true);
file << overhead << "\n";
sum += overhead;
}
cout << (sum / OP_TIMES) << " cycles" << endl;
file.close();
}
else {
cout << "Can't open file-" << CACHED_SYSTEM_CALL_OVERHEAD_FILE << endl;
}
}
int main(int argc, char *argv[])
{
unsigned long long time;
long long timeS;
time = getMeasureOverhead();
printf("Measurement overhead is %llu cycles\n", time);
time = getLoopOverhead();
printf("Loop overhead is %llu cycles per iteration\n", time);
long long callAvgs[8];
getProcedureCallOverhead(callAvgs);
printf("Procedure call overhead:\n");
printf("0 args - %lli\n", callAvgs[0]);
printf("1 args - %lli\n", callAvgs[1]);
printf("2 args - %lli\n", callAvgs[2]);
printf("3 args - %lli\n", callAvgs[3]);
printf("4 args - %lli\n", callAvgs[4]);
printf("5 args - %lli\n", callAvgs[5]);
printf("6 args - %lli\n", callAvgs[6]);
printf("7 args - %lli\n", callAvgs[7]);
timeS = getSystemCallOverhead();
printf("Syscall overhead is %lli cycles\n", timeS);
unsigned long long threadRun = getSingleThreadRunOverhead();
printf("Thread run overhead is %llu cycles\n", threadRun);
unsigned long long procRun = getSingleProcessRunOverhead();
printf("Process run overhead is %lli cycles\n", procRun);
timeS = getThreadContextSwitchOverhead(threadRun);
printf("Thread context switch overhead is %llu cycles\n", timeS);
timeS = getProcessContextSwitchOverhead(procRun);
printf("Process context switch overhead is %llu cycles\n", timeS);
exit(1);
}
