Re: [Linuxptp-users] linuxptp result doesn't match 1PPS measurement

[Richard C. <ric...@gm...>]

On Thu, Sep 08, 2022 at 06:40:26AM -0700, Richard Cochran wrote:
> On Thu, Sep 08, 2022 at 07:41:53PM +0800, Hamilton Alex wrote:
> 
> > however,  the 1pps time error is around 40 NS, which means my board is
> > ahead of the reference for about 40NS, which doesn't match the result
> > dumped by ptp4l.
> > 
> > anyone has met similar issue before?  how to debug such issue?
> 
> This is likely due to path asymmetry.

Oh, and Miroslav is correct, 9 usec path delay is huge.  It should be
only 5 ns per meter of cable.

Good luck,
Richard