[LinuxPPS] precision

[Rodolfo Giometti]

On Tue, Oct 30, 2007 at 04:40:18PM +0100, Udo van den Heuvel wrote:
> Rodolfo Giometti wrote:
> > On Tue, Oct 30, 2007 at 03:55:48PM +0100, Udo van den Heuvel wrote:
> >> Hello,
> >>
> >> About the recent reports of decreased precision:
> >>
> >> How could we determine if these changes are related to LinuxPPS or are
> >> elsewhere in the kernel?
> >> If it's LinuxPPS: what could we improve?
> >> How could one optimize the kernel for optimal performance with LinuxPPS?
> > 
> >From LinuxPPS point of view the PPS events are simply reported to the
> > userland, no computation are made on the PPS data.
> 
> Sure.
> I am not an expert and cannot determine performance differences myself
> since I only have on LinuxPPS box.
> I believe a saw a change to LinuxPPS sometime agoto record timestamps as
> soon as possible?
> If that is correct, we cannot change anything much?

Currently the pps_event() records the timestamp as soon as it is
called by the IRQ handler...

I don't see any chances how we can improve it.

Ciao,

Rodolfo

-- 

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