Re: [Linuxptp-users] phc offset explodes after a while

[Koehrer M. (ETAS/ESW5) <mat...@et...>]

Hi Richard,

> I have used the very same kernel 3.2.48 without the RT_PREEMPT patch
> using
> the same configuration.
> Also here, I got the same issue after a while (it took more than 30 minutes).
> I added some print-outs to the file clock.c in function clock_synchronize().
> Directly after the c->master_offset = tmv_sub(....) call I printed out the
> values that are used in the computation.
> Below is the related snippet from the logfile.
> There is a jump in the value of "origin" that seems to  cause the issue.
> 
I was able to catch the issue again.
Also I created a tcpdump log in parallel.
Here is the log snippet, the tcpdump file is attached.

Regards

Mathias
---- BEGIN LOG
Jan 30 15:57:34 pca ptp4l: [6636.856] ingress:1391093889615119561  origin:1391093889615118874 path_delay:734 c1:0 c2:0
Jan 30 15:57:34 pca ptp4l: [6636.856] master offset        -47 s2 freq   -6217 path delay       734
Jan 30 15:57:35 pca phc2sys: [6637.403] phc offset       451 s2 freq  +29992 delay   6572
Jan 30 15:57:35 pca ptp4l: [6637.856] ingress:1391093890615137959  origin:1391093890615137194 path_delay:734 c1:0 c2:0
Jan 30 15:57:35 pca ptp4l: [6637.856] master offset         31 s2 freq   -6153 path delay       734
Jan 30 15:57:36 pca phc2sys: [6638.403] phc offset     -2442 s2 freq  +27235 delay   6811
Jan 30 15:57:36 pca ptp4l: [6638.856] ingress:1391093891615150863  origin:1391093891615150154 path_delay:734 c1:0 c2:0
Jan 30 15:57:36 pca ptp4l: [6638.856] master offset        -25 s2 freq   -6200 path delay       734
Jan 30 15:57:37 pca phc2sys: [6639.403] phc offset     10534 s2 freq  +39478 delay   6712
Jan 30 15:57:37 pca ptp4l: [6639.855] Offset is 18446673704965374042 Line 1058
Jan 30 15:57:37 pca ptp4l: [6639.855] ingress:1391093892614699018  origin:1391164261358875858 path_delay:734 c1:0 c2:0
Jan 30 15:57:37 pca ptp4l: [6639.855] master offset -70368744177574 s2 freq -599999999 path delay       734
Jan 30 15:57:38 pca phc2sys: [6640.403] phc offset -329001709 s2 freq -500000 delay   6783
Jan 30 15:57:38 pca ptp4l: [6640.855] Offset is 18446673704965374042 Line 1055
Jan 30 15:57:38 pca ptp4l: [6640.855] Offset is 18446673705563630157 Line 1058
Jan 30 15:57:38 pca ptp4l: [6640.855] ingress:1391093894212433325  origin:1391164262358351738 path_delay:3046 c1:0 c2:0
Jan 30 15:57:38 pca ptp4l: [6640.855] master offset -70368145921459 s2 freq -599999999 path delay      3046
Jan 30 15:57:39 pca phc2sys: [6641.404] phc offset -928285857 s2 freq -500000 delay   6749
Jan 30 15:57:39 pca ptp4l: [6641.854] Offset is 18446673705563630157 Line 1055
Jan 30 15:57:39 pca ptp4l: [6641.854] Offset is 18446673706163311668 Line 1058
---- END LOG