-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 The Saturday 2007-12-08 at 01:05 +0100, Carlos E. R. wrote:
Not yet. I think I will compile the kernel tomorrow: it takes about three hours in this machine.
So, what happened Carlos. Any change?
Not yet, I couldn't... however, I have been running tests. I wrote a cronjob to compare the system clock to the cmos clock every 5 minutes, and the difference varies between 0 and 1 seconds for several hours. Then I disconnected the router, to force ntpd to be unable to connect to its peers... and not 1" error! No drift! I'm astonished. I have an email pending with some logs of this, I'll send it promptly.
The only thing I did was to force the kernel to use the 'tsc' clock instead of the 'acpi_pm' clocksource it was using:
I left the computer on all night, with no network, and... no drift! The error this morning was, surprise: 8 Dec 11:31:06 ntpd[26893]: offset 0.011621 sec freq -98.861 ppm error 0.002463 poll 7 8 Dec 11:51:44 ntpd[26893]: synchronized to 193.62..., stratum 1 8 Dec 11:51:49 ntpd[26893]: time reset +0.252153 s Less than half a second of error, with no network! This is indeed surprising. It seems that my computer works better with the 'tsc' clocksource than with the 'acpi_pm' one. Now the problem is to know why 'tsc' was rejected on boot or later. Googling for 'acpi_pm' I find references to problems similar to mine on other distros, so there is definitely a problem somewhere in the kernel. The question on what are each clock type is also asked with no answer. The 'acpi_pm.c' source says: * Driver to use the Power Management Timer (PMTMR) available in some * southbridges as primary timing source for the Linux kernel. So that's not the typical cpu, IRQ based clock! The 'tsc.c' source says nothing: * This code largely moved from arch/i386/kernel/timer/timer_tsc.c * which was originally moved from arch/i386/kernel/time.c. * See comments there for proper credits. And I have no 'arch/i386/kernel/timer/' dir at all, not 'arch/i386/kernel/time.c' file. Good grief. Free code may be good and all that, but things are difficult to find out, unless you are an insider! [...] For instance, in http://marc.info/?l=linux-kernel&m=117812987231998&w=2 (march 2007) they say the clock is lossing time when the computer is iddling - which matches my findings, too, even though mine is a desktop, i686, 32 bits. - -- Cheers, Carlos E. R. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4-svn0 (GNU/Linux) iD8DBQFHWoL1tTMYHG2NR9URArBaAJ4kcaM7fCb7LpE8OlUvCE0hv/lmagCfS+r0 JkCxmhH8V6rKcF19wvIFndo= =OFzo -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org