Re: CPU speed without rdtsc


Wojtek wrote:
Hi there!
I'm new here, so sorry if the question has appeared once :-)
I have to chceck speed of my CPU without using rdtsc. I wrote such code:
int _tmain(int argc, _TCHAR* argv[])
{
long long ile_operacji = 1000000000;
SYSTEMTIME st;
SYSTEMTIME st2;
GetSystemTime(&st);


You seem to be writing a Win32 app here, no?
If so, there is a kernel call you can make to get this information (off
the top of my head, I don't remember the API name, but I'm sure someone
else will follow up with that information).

RDTSC is becoming less and less reliable anyway. On multi-core CPUs,
different calls can return a different RDTSC counter value (if the
thread has switched affinity), so be aware of that.
Cheers,
Randy Hyde

.

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