Re: [Linuxptp-users] About ptp4l sync completed time

[Takahiro S. <tsh...@gm...>]

Hello Richard,

Thank you for the reply.

No, it is not normal.
>
> With hardware time stamping, you should get withn 0.1 usec in about
> one or two minutes.
>

OK. I see. I will check the driver again.

Here is the result of ptp4l.
After 5 sec, master offset is decreasing gradually.
I doubt the part of adjust in the ptp driver now.

time (sec) master offset (ns) adj path delay (ns)
1 60830880 0 5664
2 60821056 0 5664
3 60813078 0 4202
4 60802764 0 5076
5 -6095222 -6095222 6086198
6 32729162 30900595 6086198
7 34621386 42611568 6086198
8 36350508 50000000 4348852
9 36340812 50000000 4348852
10 36874096 50000000 3805968
11 37286637 50000000 3383795
12 37614629 50000000 3046171
13 37604965 50000000 3046171
14 37595272 50000000 3046232
15 37585167 50000000 3046673
16 37575567 50000000 3046673
17 37565746 50000000 3046862
18 37556132 50000000 3046652
19 40587180 50000000 6164
20 40577580 50000000 6164
21 40567788 50000000 6292
22 40558188 50000000 6292
23 40548557 50000000 6259
24 40539149 50000000 6259
25 40529431 50000000 6121
26 40519704 50000000 6184
27 40510104 50000000 6184
28 40500567 50000000 6089
29 40491186 50000000 5806
30 40481616 50000000 5744
31 40471957 50000000 5771
32 40462424 50000000 5672
33 40453071 50000000 5617
34 40443239 50000000 5561
35 40433989 50000000 5179
:
:
:
4393 -123348 32673175 5364
4394 -37972 32721547 5364
4395 -948 32747179 5364
4396 10444 32758287 5364
4397 11048 32762024 5176
4398 7655 32761945 4889
4399 4199 32760786 4889
4400 1863 32759710 4921
4401 903 32759308 4921
4402 133 32758809 4667
4403 199 32758915 4313
4404 135 32758911 3961
4405 -57 32758759 3769
4406 -195 32758604 3683
4407 -291 32758450 3683
4408 268 32758922 3220
4409 -201 32758533 3241
4410 -209 32758465 3249
4411 5 32758616 3099
4412 -6 32758606 3014
4413 -121 32758490 3001
4414 -107 32758467 2987
4415 -11 32758531 2987
4416 -9 32758530 2985
4417 -36 32758500 2980
4418 44 32758569 2964
4419 -20 32758519 2964
4420 -20 32758513 2964
4421 -54 32758473 2966


> > 2. Can I speed up the time till sync completed?
>
> The clock servo (in pi.c) has a PI controller, and its constants do
> affect the convergence performance.
>
> However, I think you have errors in the time stamps, or missing time
> stamps.
>
> HTH,
> Richard
>
I see. I will check it too.

Thanks and Best regards,
Takahiro Shimizu