Miroslav, I’m sorry, I didn’t mean to imply that the spikes were an unrelated to the ordering issue. I do believe that the spikes are related to the hardware timestamp ordering issue.
I’ll try to set up some of the tests you’ve requested later this evening, but it may take a day for me to have results. Denny > On Nov 16, 2016, at 00:53, Miroslav Lichvar <mlich...@redhat.com> wrote: > > On Tue, Nov 15, 2016 at 08:24:37PM -0800, Denny Page wrote: >> With the latest drop in the repo, I’m still seeing the wild spikes in the >> standard deviation with hardware time stamping against the fast responding >> hardare units. I'm also still seeing a better base deviation using software >> timestamps against them as well. >> >> I do see better results with hardware time stamping when doing chrony to >> chrony, but I believe that this is a result of the general purpose computers >> being a bit slower to respond than the dedicated hardware units. > > Hm, the fix helped with the spikes I was seeking. Did we rule out the > possibility that in your case the spikes are due to the other issue with > out-of-order HW timestamps? Could you try it with this patch to make > sure only measurements with HW timestamps are used? > > --- a/ntp_core.c > +++ b/ntp_core.c > @@ -1434,6 +1434,9 @@ receive_packet(NCR_Instance inst, NTP_Local_Address > *local_addr, > prevent a synchronisation loop */ > testD = message->stratum <= 1 || REF_GetMode() != REF_ModeNormal || > pkt_refid != UTI_IPToRefid(&local_addr->ip_addr); > + > + if (inst->local_tx.source != NTP_TS_HARDWARE || rx_ts->source != > NTP_TS_HARDWARE) > + testB = 0; > } else { > offset = delay = dispersion = 0.0; > sample_time = rx_ts->ts; > > -- > Miroslav Lichvar > > -- > To unsubscribe email chrony-dev-requ...@chrony.tuxfamily.org with > "unsubscribe" in the subject. > For help email chrony-dev-requ...@chrony.tuxfamily.org with "help" in the > subject. > Trouble? Email listmas...@chrony.tuxfamily.org. > -- To unsubscribe email chrony-dev-requ...@chrony.tuxfamily.org with "unsubscribe" in the subject. For help email chrony-dev-requ...@chrony.tuxfamily.org with "help" in the subject. Trouble? Email listmas...@chrony.tuxfamily.org.