On Thu, Mar 27, 2014 at 2:27 PM, John Stultz <john.stu...@linaro.org> wrote: > On Thu, Mar 27, 2014 at 12:52 PM, Andy Lutomirski <l...@amacapital.net> wrote: >> On 03/27/2014 04:02 AM, Clemens Ladisch wrote: >>> Feng Tang wrote: >>> The help text still says: >>> | You can safely choose Y here. [...] >>> | Choose N to continue using the legacy 8254 timer. >>> >>> Are these statements still true for those platforms? >> >> They aren't true for modern desktop and server platforms -- the TSC is >> used regardless of hpet availability. > > While I suspect the comment above is in relation to the non-apic > timer. But with respect to timekeeping, our point is true assuming the > TSC isn't mucked up by the BIOS. My 1yr old i7-3930k single socket > system still has some wonky BIOS bug that offsets the boot core's TSC. > And that's intel's bios, so I can only imagine other vendors have > found other ways to cause trouble.
Is this, perhaps, an MSI X79A-GD65 (8D) (MS-7760)? If so, there's a fixed BIOS. > > So yea, the hpet availability for timekeeping is still important, as > the TSC can still be problematic. Is HPET really that much better than acpi_pm? I can read my HPET in ~584ns (vdso) or ~649ns (syscall) and my acpi_pm in 753ns. So it's better, but not by a whole lot. But yes, I see no good reason to disable it, except specifically on systems where there are known bugs. > > thanks > -john -- Andy Lutomirski AMA Capital Management, LLC -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/