On Tue, 2006-11-28 at 21:46 -0200, Alexandre Pereira Nunes wrote: > Hi, > > with default boot I got tsc clocksource selected on an debian's > 2.6.18-3-k7 SMP build (but UP machine). ntp keeps bothering me with this > message: > frequency error 512 PPM exceeds tolerance 500 PPM
Hmmm. Could you send me your dmesg? Also what frequency is your cpu? Also does booting w/ "noapic" change the behavior? > If I remove ntp's drift file and restart, it goes fine for a while and > then it goes with that behaviour again. > If I remove ntp's drift file, then do a: echo acpi_pm > >/sys/devices/system/clocksource/clocksource0/available_clocksource ; I think you mean "current_clocksource" there... > and then restart ntp, it goes fine "forever". > > Any toughs, something I should look at? > > I'll be glad to give more feedback. > > I don't know if that happened with 2.6.17, but I'm pretty sure that with > 2.6.16 it was fine. Yea, its likely the generic timekeeping changes for i386. Previously (pre-2.6.18) it probably defaulted to the acpi pm timer and was fine. The new code is a bit more aggressive in trying to use the TSC. As a short term workaround, you can put "clocksource=acpi_pm" on your grub line and that will force the clocksource at boot. thanks -john - 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/
