Re: TSC Problems (warp between CPUs)

[Adrian Vasile]

Alex,

Have you managed to fix this issue? I'm seeing the same on an Asus X99
Deluxe board with both 5930K and 5960X and the latest BIOS as of today
(0904).
I had some hopes of linux-3.17 working around this but it did not help.
Asus support is disappointing, I don't think they will ever fix this.

I'm wondering if it's worth trying a different motherboard, any
recommendations?

Thank you.

Regards,
Adrian

On 31/12/13 22:24, Alex wrote:
> A Happy new year to all :)
>
> Just wondering whether anyone has any ideas on how I could force the
> TSC to resync?
>
> Starting to get a bit desperate. The motherboard manufacturers support
> is useless.... They keep telling me to install Windows *groan*. I dont
> think there is any easy way to expose what clock source the OS is
> using even in windows.
>
> I even tried firing an email at the AmiBios guys. I think I have
> exhausted every avenue of help as far as the hardware goes.
>
> Any suggestions?
>
> Kind regards,
> Alex
>
> On 2013-12-29 11:21, Alex wrote:
> > On 2013-12-29 01:35, One Thousand Gnomes wrote:
> > > > not guaranteed to be precise. For example a SMI (System Management
> > > > Interrupt) could interrupt the software flow that is attempting to
> > > > write
> > > > the time-stamp counter immediately prior to the WRMSR. This could mean
> > > > the value written to the TSC could vary by thousands to millions of
> > > > clocks.
> > >
> > > Yes SMI is a disaster area for any real time activity (and many other
> > > things ;) ), but many systems actually make little use of it,
> > > especially
> > > once the USB is owned by the OS.
> > >
> > > For synchronization you can retry the sync if it isn't within an
> > > acceptable range. The odds of getting an SMI mid sync setup should be
> > > very very low, so the odds of repeating the failure several times
> > > should
> > > be negligible and after a few tries you could give up and assume the
> > > hardware is buggered then fall back to HPET.
> >
> > Hi Alan,
> >
> > The sync retry sounds like an interesting strategy but is outside my
> > knowledge
> > scope as a regular end user (I do have a reasonable understanding of
> > C and can patch+
> > recompile) but I lack the architecture knowledge to implement a patch
> > to do this.
> >
> > Any suggestions?

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