ja...@peroulas.com said: > Any ideas on where I can look to track down the discrepancy?
Dig out the kernel sources. There are 2 sources of error. One is the calibration routine. It's comparing the CPU cycle counter with another counter that runs at a specified frequency. I think recent kernels have cleaned up this area but it used to generate a lot of noise. Boot a system several times and you will get several different answers, off by up to 100 ppm. Grep your log file looking for things like: Detected 430.931 MHz processor. See if you get the same answer each time you boot. The other possible error is just the main timekeeping routines. Maybe some constant is off a bit. Unless somebody does your type of measurement, nobody would notice as long as it was close enough that NTP could fix it. (Who but a time-nut would care if the crystal was off by 33 ppm or 43 ppm?) > but it seldom departs from -33ppm by more than 1 or 2 ppm... What do you expect? Ballpark is 1 ppm/C. How stable is your temperature? -- These are my opinions. I hate spam. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.