JD wrote: > > On 09/27/2010 07:34 AM, Wade Hampton wrote: > >> Did you look at using the RDTSC instruction to read the >> cycle counter? >> >> http://en.wikipedia.org/wiki/Time_Stamp_Counter >> >> Sample this over an interval to get an estimate >> of the clock frequency based on this counter. >> >> __inline__ unsigned long long int rdtsc() >> { >> unsigned long long int x; >> __asm__ volatile (".byte 0x0f, 0x31" : "=A" (x)); >> return(x); >> } >> >> I use gettimeofday() calls to check the wall-clock time, >> usleep(n) to sleep for a long time (second or more), >> and rdtsc to compute the cycles.... Seems to work >> well. >> >> Cheers, >> -- >> Wade Hampton >> > Thank you very much Wade. > I confirm that using rdtsc, the delta in tsc values, divided by 60 > (using nanosleep) > is 798283074.9833333333 ticks per second, which is almost iddentical > to what is reported by cpuinfo: > cpu MHz : 798.244 > > No matter what the load factor on the machine, even when the load > reached 5 or 6, > it is the same value. > Well, that's what you get for buying a laptop from a crappy manufacturer > that has put in it a fixed unprogrammable clock (oscillator), and put in a > lame BIOS that provides no hooks for setting C2 C3 ...etc. > I will certainly steer friends and family away from this manufacturer. > > > I find the whole idea of a manufacturer purposely sabotaging a computer in this manner just disgraceful. This one really takes the cake since "cool and quiet" and "powernow" was a big marketing scheme back then. You would think that the bios would at least have something to say about it I wonder if the machine in question was on windows if the cool and quiet drivers would have something to enable/ disable them by software? But then again if Bios does not support then that would be a no show too... Very bad manufacturing screw up Michael -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
