(my message was rejected... why?) Hi ramesh,
I don't know your system's precision. I tuned the step_threshold and first_step_threshold values following this criteria: Given my system's precision (<X ns) and the "acceptable" noise (<Yns) I set the first_step_threshould to my target alignment (Xns ... 1ns is a good value in most cases) for the first attempt. The noise is the maximum/sum between the network noise, your system "natural" noise and the residual noise after the clock step. For example, my hypothetical system is able to track up to 2ns precision, the network introduces a noise about 5ns and after the clock_step my system, in the worst case, has about ~100ns of error w.r.t. the target 0ns offset alignment. From these values I decided to set the step_threshold to a value circa 100ns (100ns +10%). This value will permit to keep the tracking just after the clock_step and be robust to network and system noise. (Edit). Another observation is your system's in order to compensate the offset (your is 900000000ppm) just using DCO (time_need_to_align = deltaOffset / maxFreqAdj) A value less than 100ns will create a potentially unbounded sequence of sync faults after the first clock_step. These are my suggestions... ciao luigi Il giorno lun 8 nov 2021 alle ore 12:06 ramesh t via Linuxptp-devel <linuxptp-devel@lists.sourceforge.net> ha scritto: > > hi, > > Rms value of PTP slave/support is taking longer duration (1-2 hours) to come > back to single/two digit value. > > Oct 29 01:21:37 ptp4l_slave: [2115639.889] handle_state_decision_event > PS_LISTENING > Oct 29 01:21:37 ptp4l_slave: [2115640.178] selected best master clock > 28affd.fffe.e5de3f > Oct 29 01:21:37 ptp4l_slave: [2115640.178] handle_state_decision_event > PS_SLAVE > Oct 29 01:21:37 ptp4l_slave: [2115640.178] port 1: LISTENING to UNCALIBRATED > on RS_SLAVE > Oct 29 01:21:37 ptp4l_slave: [2115640.178] PS_SLAVE: port_e2e_transition > Oct 29 01:21:37 ptp4l_slave: [2115640.242] port 1: UNCALIBRATED to SLAVE on > MASTER_CLOCK_SELECTED > Oct 29 01:21:37 ptp4l_slave: [2115640.242] PS_SLAVE: port_e2e_transition > Oct 29 01:21:38 ptp4l_slave: [2115640.370] rms 10301244690663 max > 15341881743901 freq -900000000 +/- 0 delay -16376519 +/- 2081539 > Oct 29 01:21:39 ptp4l_slave: [2115641.370] rms 8782943571542 max > 8783365601487 freq -900000000 +/- 0 delay -13254922 +/- 1790307 > Oct 29 01:21:39 ptp4l_slave: [2115641.434] selected best master clock > 28affd.fffe.e5de3f > Oct 29 01:21:39 ptp4l_slave: [2115641.435] handle_state_decision_event > PS_SLAVE > Oct 29 01:21:40 ptp4l_slave: [2115642.374] rms 8782045654609 max > 8782467416190 freq -900000000 +/- 0 delay -10871120 +/- 1851783 > > Oct 29 03:25:03 ptp4l_slave: [2123045.451] rms 2119240296684 max > 2119664072935 freq -900000000 +/- 0 delay -11533365 +/- 1437648 > > We are using below values in the ptp config file. > step_threshold 0.0 > first_step_threshold 0.00002 > max_frequency 900000000 > clock_servo pi > sanity_freq_limit 200000000 > > Can you please suggest what should be proper configuration? > > regards, > Ramesh > > > _______________________________________________ > Linuxptp-devel mailing list > Linuxptp-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linuxptp-devel -- Luigi 'Comio' Mantellini My Professional Profile "UNIX is very simple, it just needs a genius to understand its simplicity." [cit.] _______________________________________________ Linuxptp-devel mailing list Linuxptp-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linuxptp-devel
