[LinuxPPS] PPS kernel discipline

[Thorsten Mühlfelder]

On Wed, 25 Mar 2009 16:54:57 +0100
Udo van den Heuvel <udovdh at xs4all.nl> wrote:

> Thorsten Mühlfelder wrote:
> > When kernel PPS support is enabled, the PPS driver can direct the signal 
> > directly to the kernel. Note that the PPS driver does not normally enable 
> > the PPS kernel, since performance is generally better with older systems. 
> 
> So it is optional.
> Disabled by default.
> And without that stuff works(TM).
> So it is for improving even more.

It is part of the PPSAPI http://www.cis.udel.edu/~mills/ntp/html/kernpps.html
and works with BSD and PPSkit.

And see what David Mills says himself:
"Somehow using an HP 5071 to discipline the time without kernel support
seems bizarre."
http://groups.google.com/group/comp.protocols.time.ntp/browse_frm/thread/1f2a90c9e4456169?hl=en

The ntpd docs often are quite outdated, so I don't know if it is still
disabled by default.

> Is a VIA Ek8000 quick enough?

I think any x86 CPU at 100 MHz or above can be rated pentium class ;-)