Re: [Linuxptp-devel] [RFC 0/1] Adding support for AVnu Automotive Profile

[Patel, V. <ved...@in...>]

On Thu, 2018-07-19 at 08:08 -0700, Richard Cochran wrote:
> On Mon, Jul 16, 2018 at 02:34:46PM -0700, Vedang Patel wrote:
> > 
> > - Switching Sync message interval and pdelay message intervals to a
> > lower value
> >   once system stabilizes (Sections 6.2.3.1 and 6.2.3.2 in [1]).
> This is an interesting option to have, all on its own.
> 
A very basic question: What is the best way for master to determine the
system has stabilized and change the sync interval? In the original
plan, the slave would know and then it would send a signaling message
to increase the interval.
> > 
> >   This will also
> >   add support for Message Interval request TLV (Section 10.5.4 in
> > [2]).
> This is a complete waste of time, IMHO.  The whole idea of this
> "profile" is that everything is statically configured.  Why on earth
> should slaves then adjust the intervals later on?
> 
> Nobody needs this.
> 
> > 
> > - Option to save some properties like neighborRateRatio when the
> > program exits.
> >   (Sections 6.2.2.2 and 6.2.2.3 in [1])
> No need to save on exit.  If you like, script pmc to do this for you.
> However, a pre-seeded configuration option makes sense to add.
> 
Ok will add a config option for the rate ratios.
> > 
> > - Option to continue adjusting the clock even when slave does not
> > receive Sync
> >   messages from master. (Section 6.3 bullet 4 sub bullet 6 -- lines
> > 228 to 230)
> Please explain exactly what you have in mind.
>  
Here, I was just planning to adjust the clock such that it keeps on
advancing based on last known value of cumulativeScaledRateOffset.

But, after looking a bit more into the code, it looks like this might
already be done. Need to look at the code a little more closely to know
for sure.

Thanks,
Vedang
> Thanks,
> Richard
>