[Linuxptp-users] Software timestamping delay - master offset drift

Thu, 11 May 2023 09:06:03 -0700

I had already notice this while trying to solve the clock sync issue of the other thread. 

Test setup is two Fitlet PCs, connected point-to-point.
The master offset increases, non monotonically but with a very definite trend, whether with or without the step_threshold parameter. 

$ uname -srvm
Linux 5.15.0-70-generic #77~20.04.1-Ubuntu SMP Wed Apr 5 09:38:34 UTC 2023 x86_64 

$ ptp4l -v
3.1-00246-g5498f74

What am I missing?

$ sudo ptp4l -S -m -q --clientOnly=1 --step_threshold=0.01 -i enp3s0
ptp4l[17804.187]: port 1 (enp3s0): INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[17804.188]: port 0 (/var/run/ptp4l): INITIALIZING to LISTENING on INIT_COMPLETE ptp4l[17804.188]: port 0 (/var/run/ptp4lro): INITIALIZING to LISTENING on INIT_COMPLETE 
ptp4l[17805.578]: port 1 (enp3s0): new foreign master 0001c0.fffe.1a3e8e-1
ptp4l[17809.579]: selected best master clock 0001c0.fffe.1a3e8e
ptp4l[17809.579]: foreign master not using PTP timescale
ptp4l[17809.579]: port 1 (enp3s0): LISTENING to UNCALIBRATED on RS_SLAVE
ptp4l[17810.584]: master offset     159453 s0 freq +100000000 path delay    216530 ptp4l[17811.584]: master offset     204915 s0 freq +100000000 path delay    216530 ptp4l[17812.585]: master offset     253667 s0 freq +100000000 path delay    210875 ptp4l[17813.585]: master offset     216052 s0 freq +100000000 path delay    222827 ptp4l[17814.585]: master offset     218133 s0 freq +100000000 path delay    222827 ptp4l[17815.585]: master offset     238977 s0 freq +100000000 path delay    218369 ptp4l[17816.585]: master offset     243903 s0 freq +100000000 path delay    218369 ptp4l[17817.585]: master offset     161090 s0 freq +100000000 path delay    218369 ptp4l[17818.585]: master offset     243281 s0 freq +100000000 path delay    218369 ptp4l[17819.585]: master offset     252487 s0 freq +100000000 path delay    218369 ptp4l[17820.585]: master offset     243551 s0 freq +100000000 path delay    215088 ptp4l[17821.586]: master offset     253522 s0 freq +100000000 path delay    216985 ptp4l[17822.586]: master offset     254771 s0 freq +100000000 path delay    216985 ptp4l[17823.586]: master offset     236767 s0 freq +100000000 path delay    216985 ptp4l[17824.586]: master offset     260883 s0 freq +100000000 path delay    215088 ptp4l[17825.586]: master offset     231376 s0 freq +100000000 path delay    215088 ptp4l[17826.586]: master offset     279783 s1 freq +100000000 path delay    208463 ptp4l[17827.586]: master offset      -4948 s2 freq +99999500 path delay    208463 ptp4l[17827.586]: port 1 (enp3s0): UNCALIBRATED to SLAVE on MASTER_CLOCK_SELECTED ptp4l[17828.586]: master offset     -26034 s2 freq +99997366 path delay    208463 ptp4l[17829.586]: master offset       9262 s2 freq +100000000 path delay    196545 ptp4l[17830.587]: master offset     -64129 s2 freq +99993492 path delay    196545 ptp4l[17831.587]: master offset       8086 s2 freq +100000000 path delay    180968 ptp4l[17832.587]: master offset      19802 s2 freq +100000000 path delay    180968 ptp4l[17833.587]: master offset      25994 s2 freq +100000000 path delay    196545 ptp4l[17834.587]: master offset      33958 s2 freq +100000000 path delay    180968 ptp4l[17835.587]: master offset     -43154 s2 freq +99995546 path delay    187560 ptp4l[17836.587]: master offset      24553 s2 freq +100000000 path delay    187560 ptp4l[17837.587]: master offset      22863 s2 freq +100000000 path delay    209257 ptp4l[17838.588]: master offset      -6513 s2 freq +99999204 path delay    214778 ptp4l[17839.588]: master offset      25468 s2 freq +100000000 path delay    212728 ptp4l[17840.588]: master offset      31602 s2 freq +100000000 path delay    206895 ptp4l[17841.588]: master offset      31784 s2 freq +100000000 path delay    206895 ptp4l[17842.588]: master offset      14909 s2 freq +100000000 path delay    211621 ptp4l[17843.588]: master offset      25457 s2 freq +100000000 path delay    211621 ptp4l[17844.588]: master offset       5632 s2 freq +100000000 path delay    211621 ptp4l[17845.589]: master offset      43463 s2 freq +100000000 path delay    208242 ptp4l[17846.589]: master offset      42612 s2 freq +100000000 path delay    208242 ptp4l[17847.589]: master offset      22200 s2 freq +100000000 path delay    211621 ptp4l[17848.589]: master offset      26093 s2 freq +100000000 path delay    211507 ptp4l[17849.589]: master offset     -67089 s2 freq +99993079 path delay    211507 ptp4l[17850.589]: master offset      18941 s2 freq +100000000 path delay    211507 ptp4l[17851.589]: master offset      53578 s2 freq +100000000 path delay    211507 ptp4l[17852.589]: master offset      41217 s2 freq +100000000 path delay    212352 ptp4l[17853.589]: master offset     -29075 s2 freq +99996852 path delay    212352 ptp4l[17854.590]: master offset      63911 s2 freq +100000000 path delay    212352 ptp4l[17855.590]: master offset      48070 s2 freq +100000000 path delay    213941 ptp4l[17856.590]: master offset     -15308 s2 freq +99998213 path delay    211507 ptp4l[17857.590]: master offset      52932 s2 freq +100000000 path delay    211507 ptp4l[17858.590]: master offset      72178 s2 freq +100000000 path delay    210398 ptp4l[17859.590]: master offset     -25048 s2 freq +99997214 path delay    211507 ptp4l[17860.590]: master offset      59028 s2 freq +100000000 path delay    210398 ptp4l[17861.591]: master offset      83153 s2 freq +100000000 path delay    210398 ptp4l[17862.591]: master offset     -15561 s2 freq +99998147 path delay    209111 ptp4l[17863.591]: master offset      87904 s2 freq +100000000 path delay    206645 ptp4l[17864.591]: master offset      14074 s2 freq +100000000 path delay    206645 ptp4l[17865.591]: master offset     110231 s2 freq +100000000 path delay    194703 ptp4l[17866.591]: master offset      23757 s2 freq +100000000 path delay    194703 ptp4l[17867.591]: master offset      20245 s2 freq +100000000 path delay    179716 ptp4l[17868.591]: master offset      18863 s2 freq +100000000 path delay    179716 ptp4l[17869.591]: master offset      95764 s2 freq +100000000 path delay    174219 ptp4l[17870.591]: master offset      49927 s2 freq +100000000 path delay    174219 ptp4l[17871.592]: master offset     140161 s2 freq +100000000 path delay    172870 ptp4l[17872.592]: master offset      26294 s2 freq +100000000 path delay    174498 ptp4l[17873.592]: master offset      34713 s2 freq +100000000 path delay    172870 ptp4l[17874.592]: master offset      24618 s2 freq +100000000 path delay    172870 ptp4l[17875.592]: master offset     152488 s2 freq +100000000 path delay    171713 ptp4l[17876.592]: master offset      32740 s2 freq +100000000 path delay    174498 ptp4l[17877.592]: master offset     118871 s2 freq +100000000 path delay    171713 ptp4l[17878.592]: master offset     160898 s2 freq +100000000 path delay    170332 ptp4l[17879.593]: master offset     157665 s2 freq +100000000 path delay    171767 ptp4l[17880.593]: master offset      19963 s2 freq +100000000 path delay    217720 ptp4l[17881.593]: master offset      93649 s2 freq +100000000 path delay    217720 ptp4l[17882.593]: master offset     108074 s2 freq +100000000 path delay    220966 ptp4l[17883.593]: master offset      87514 s2 freq +100000000 path delay    220966 ptp4l[17884.593]: master offset      77271 s2 freq +100000000 path delay    215470 ptp4l[17885.593]: master offset     114914 s2 freq +100000000 path delay    215470 ptp4l[17886.593]: master offset      98124 s2 freq +100000000 path delay    215470 ptp4l[17887.593]: master offset     129160 s2 freq +100000000 path delay    215470 ptp4l[17888.594]: master offset     100582 s2 freq +100000000 path delay    215470 ptp4l[17889.594]: master offset     125095 s2 freq +100000000 path delay    215110 ptp4l[17890.594]: master offset     124738 s2 freq +100000000 path delay    215110 ptp4l[17891.594]: master offset     106051 s2 freq +100000000 path delay    215500 ptp4l[17892.594]: master offset     126470 s2 freq +100000000 path delay    215500 ptp4l[17893.594]: master offset     131971 s2 freq +100000000 path delay    215500 ptp4l[17894.594]: master offset      48569 s2 freq +100000000 path delay    215500 ptp4l[17895.594]: master offset     134499 s2 freq +100000000 path delay    215500 ptp4l[17896.595]: master offset     134927 s2 freq +100000000 path delay    215771 ptp4l[17897.595]: master offset      57682 s2 freq +100000000 path delay    219586 ptp4l[17898.595]: master offset     137885 s2 freq +100000000 path delay    214427 ptp4l[17899.595]: master offset     141448 s2 freq +100000000 path delay    213856 ptp4l[17900.595]: master offset     157021 s2 freq +100000000 path delay    208183 ptp4l[17901.595]: master offset     127072 s2 freq +100000000 path delay    212943 ptp4l[17902.595]: master offset     153837 s2 freq +100000000 path delay    206355 ptp4l[17903.595]: master offset      86728 s2 freq +100000000 path delay    212943 ptp4l[17904.595]: master offset      53300 s2 freq +100000000 path delay    197715 
...
ptp4l[18856.714]: master offset    1642006 s2 freq +100000000 path delay    210466 ptp4l[18857.714]: master offset    1638704 s2 freq +100000000 path delay    210466 ptp4l[18858.714]: master offset    1562520 s2 freq +100000000 path delay    209583 ptp4l[18859.715]: master offset    1658159 s2 freq +100000000 path delay    205885 ptp4l[18860.715]: master offset    1658522 s2 freq +100000000 path delay    196826 ptp4l[18861.715]: master offset    1548773 s2 freq +100000000 path delay    196826 ptp4l[18862.715]: master offset    1661950 s2 freq +100000000 path delay    185949 ptp4l[18863.715]: master offset    1671314 s2 freq +100000000 path delay    185949 ptp4l[18864.715]: master offset    1674822 s2 freq +100000000 path delay    185949 ptp4l[18865.715]: master offset    1596681 s2 freq +100000000 path delay    185949 ptp4l[18866.716]: master offset    1666690 s2 freq +100000000 path delay    185949 ptp4l[18867.716]: master offset    1670159 s2 freq +100000000 path delay    185949 ptp4l[18868.716]: master offset    1649541 s2 freq +100000000 path delay    196826 ptp4l[18869.716]: master offset    1558798 s2 freq +100000000 path delay    196826 ptp4l[18870.716]: master offset    1688908 s2 freq +100000000 path delay    185949 ptp4l[18871.716]: master offset    1666295 s2 freq +100000000 path delay    185949 ptp4l[18872.716]: master offset    1668525 s2 freq +100000000 path delay    185635 ptp4l[18873.717]: master offset    1673801 s2 freq +100000000 path delay    200040 




_______________________________________________
Linuxptp-users mailing list
Linuxptp-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/linuxptp-users

Reply via email to