My oldish AMD K7-800's clock began falling behind after
rebooting from 2.6.20 (and 109 days uptime with a spotless
clock) into 2.6.22; time lost is about four minutes each hour.
Turns out that 2.6.22 marks my TSC as unstable and starts
using PIT instead. Rebooting 2.6.22 with clocksource=tsc
gets the original stable system time back.
Not sure whether this is supposed to be the default way of
fixing the issue on older machines, though; if anyone sees
a problem with this, I'm up for providing more information.
[EMAIL PROTECTED] ~]# cd /sys/devices/system/clocksource/clocksource0/
[EMAIL PROTECTED] clocksource0]# cat available_clocksource
pit jiffies tsc
[EMAIL PROTECTED] clocksource0]# cat current_clocksource
tsc
[EMAIL PROTECTED] clocksource0]# uname -a
Linux donkey 2.6.22 #1 PREEMPT Mon Jul 9 13:26:38 CEST 2007 i686
athlon i386 GNU/Linux
[EMAIL PROTECTED] clocksource0]# cat /proc/cpuinfo
processor : 0
vendor_id : AuthenticAMD
cpu family : 6
model : 4
model name : AMD Athlon(tm) Processor
stepping : 2
cpu MHz : 800.068
cache size : 256 KB
fdiv_bug : no
hlt_bug : no
f00f_bug : no
coma_bug : no
fpu : yes
fpu_exception : yes
cpuid level : 1
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca
cmov pat pse36 mmx fxsr syscall mmxext 3dnowext 3dnow
bogomips : 1603.17
clflush size : 32
thanks, ciao,
--alessandro
"Did you get married but forgot to get divorced ?"
(Danny and Dusty, 'The Good Old Days')
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
