David Woolley <[EMAIL PROTECTED]> writes:
>Unruh wrote:
>>
>> This is in the clock_filter algorithm. It selects the sample of the last 8
>> which has the lowest delay (suitably aged) If that sample is the most
>Yes. That's what I am talking about. Specifically clock_filter in
>ntp_proto.c.
>> recent, then it is actually used. Otherwise nothing is used that that
>> clokck measuremnt is tossed. Once it has a measurement sucnh that the
>> latest sample aslo has the least delay then that sample is passed to the
>> clock selection process.
>This is not what happens in RFC 1305 or ntpd 4.2.0.
>>
>> NO I am not talking about the clock selection process. It is teh
>Nor am I.
>> clock_filter which occurs before the clock selection algorithm comes into
>> play.
>/*
> * clock_filter - add incoming clock sample to filter register and run
> * the filter procedure to find the best sample.
> */
>void
>clock_filter(
>....
> /*
> * Sort the samples in both lists by distance.
> */
> for (i = 1; i < NTP_SHIFT; i++) {
>....
Under ... is the line
dst[i]=peer->filter_delay[j]
which is the typical assignment.
Ie, the peer->filterdelay is the distance
> /*
> * If no acceptable samples remain in the shift register,
> * quietly tiptoe home leaving only the dispersion. Otherwise,
> * save the offset, delay and jitter average. Note the jitter
> * must not be less than the system precision.
> */
> if (m == 0)
> return;
> etemp = fabs(peer->offset - peer->filter_offset[k]);
> dtemp = sqrt(peer->jitter);
> peer->offset = peer->filter_offset[k];
> peer->delay = peer->filter_delay[k];
> if (m > 1)
> jit /= m - 1;
> peer->jitter = max(jit, SQUARE(LOGTOD(sys_precision)));
> /*
>Guess I'd better check that this hasn't been broken in 4.2.4.....
>There are quite a lot of changes there, but the basic structure seems to
>be the same, i.e. it is based on distance, not delay, and based on
>sorting the full list.
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