system clock running 4% fast
Since I built my new amd64 host, my system clock is borked. It runs about
4% fast-- gaining an hour a day. This is way to much gain for ntpd to keep
up with. To compensate I've had to set adjtimex --tick 9600, which
approximately corrects for the drift.
This would be tolerable, except that the drift rate isn't constant. It's
all over the place. Right after I boot it's stable at about -50 PPM, but
then after a few hours it suddenly goes nuts. Look at the adjustments
ntpdate has to make when I run it once a minute:
20 Mar 05:05:58 ntpdate: step time server 188.8.131.52 offset
20 Mar 05:06:55 ntpdate: step time server 184.108.40.206 offset
20 Mar 05:07:53 ntpdate: step time server 220.127.116.11 offset
20 Mar 05:08:51 ntpdate: step time server 18.104.22.168 offset
20 Mar 05:09:48 ntpdate: step time server 22.214.171.124 offset
20 Mar 05:10:45 ntpdate: step time server 126.96.36.199 offset
20 Mar 05:11:42 ntpdate: step time server 188.8.131.52 offset
No wonder ntpd can't keep up. The drift rate is all over the place.
I'm running a custom 64-bit kernel 2.6.15. CPU is Athlon64 X2 4200+,
chipset is nForce4.
Many people are reporting problems related to time with the 2.6.15 kernel on
A search for "amd64 linux clock" turns them up. However, 80% or more of the
discussion seems to be about the "AMD/ATI bug", which applies to the
combination of AMD processors with some ATI chipsets (not sure which one). I
don't have an ATI chipset. Still, I've tried all of the following boot
parameters that people have recommended for this problem:
disable_timer_pin_1 (my host won't boot)
I also disabled CPU frequency spread spectrum in the BIOS. The result is
always the same-- the clock is stable after I boot, but a few hours later it
goes nuts again.
Help! How can I fix my system clock? Do I a hardware problem? How can I
tell? Any help would be greatly appreciated.