Re: [Linuxptp-devel] [PATCH RFC 4/6] clock: set sample weight.

[Miroslav L. <mli...@re...>]

On Mon, Feb 16, 2015 at 08:48:15PM +0100, Richard Cochran wrote:
> On Fri, Feb 13, 2015 at 01:56:16PM +0100, Miroslav Lichvar wrote:
> > +	if (sync_delay_rate <= 0 && servo_weight_samples(c->servo)) {
> > +		/* Get new sample delay with updated t1 and t2 */
> > +		sample_delay = clock_get_sample_delay(c);
> > +
> > +		if (sample_delay > 0 && c->path_delay > 0) {
> > +			weight = (double)c->path_delay / sample_delay;
> > +			if (weight > 1.0)
> > +				weight = 1.0;
> > +			pr_debug("delay sample %9" PRId64 " filtered %9" PRId64
> > +				 " weight %f",
> > +				 sample_delay, c->path_delay, weight);
> > +			c->path_delay = sample_delay;
> 
> So now, c->path_delay is set once in clock_path_delay() using
> averaging, and here the averaged value is used for the ratio, but then
> you clobber c->path_delay with the new value?

Yes, I thought the displayed delay should correspond to the offset and
not mix the sample offset with filtered delay. Maybe it would be
cleaner to add a new field to the clock structure for this?

-- 
Miroslav Lichvar