[LinuxPPS] Nanosecond timing.

[clemens at dwf.com]

Earlier this year, someone posted all the things that were needed to
get to nano-second timing linuxPPS and ntp.

It would seem that we are almost there.

The linuxPPS changes are either in, or almost in the kernel, and
Fedora 11 (plus other distributions) have glibc 2.10.1 which was
supposed to fix all the other problems.  (OK, there was still
MOD_NANO and MOD_TAI, but those are just editorial changes.)

Could whoever it was that checked the fixes in glibc take another
look and see if they all made it into 2.10.1?

Im running with the above, and it just doesnt seem right yet.
Although the timing is 'tighter' than it was before, there is still
a good chance of seeing an offset of the timestamp of 1us+ on either
side of the 'real' time.

At some point you get to the point where ntps timestamp is competing 
with the timing of the other interrupts on your machine, but I dont
think that Im there yet.

-- 

                                        Reg.Clemens
                                        reg at dwf.com