[ntp:questions] Preffered OS for a GPS based stratum 1

Rick Jones rick.jones2 at hp.com
Fri Oct 31 22:59:31 UTC 2008

Kevin Oberman <oberman at es.net> wrote:
> Seconded. FreeBSD has taken ntp and timing as a priority for a very
> long time. I know that back in the days when BSD was still being
> developed at Berkeley, they counted the instructions used by the PPS
> kernel code and then used the clock frequency to correct the time
> for that delay.

I'd have thought that it wasn't the instruction count that mattered
but the cycle count?  Admittedly, instructions/frequency is closer
than nothing but given that a single cache miss is O(100)
instructions...  so, snap CR16 (PA-RISC interval counter) or its
equivalent (assuming there is one and reading it isn't too nasty) on
entry and exit.

rick jones
The computing industry isn't as much a game of "Follow The Leader" as
it is one of "Ring Around the Rosy" or perhaps "Duck Duck Goose." 
                                                    - Rick Jones
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

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