>On recent Linux kernels, I think the drift file is always bad after reboot. >HZ=100, no dynamic ticks aka tickless system (CONFIG_NO_HZ not set). I think >I even tried with a kernel command line option lpj= but it didn't help. >If the system is rebooted, ntpd stabilizes to a new different drift value.
That's a bug in the TSC calibration code. grep your /var/log/messages* for "Detected". You will find things like thsi: Jan 4 11:21:49 shuksan kernel: Detected 2793.137 MHz processor. Jan 4 21:30:43 shuksan kernel: Detected 2793.209 MHz processor. Jan 22 09:32:20 shuksan kernel: Detected 2793.139 MHz processor. The differences in the bottom bits turn into different drift values. Recent Linux kernels use the TSC for timekeeping. (At least on the systems I work with.) There may be a simple command line option to use another chunk of hardware. -- These are my opinions, not necessarily my employer's. I hate spam. _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions
