"the fundamental difficulty of solving this problem at scale and how we solved it"
Time is hard and the funny thing is - it's relative! Anyone who says they have "solved" time is delusional. The best you can do is reduce errors and problems related to timekeeping to an acceptable level.
I've "solved" time at work with three Raspberry Pis with GPS boards/hats and aerials. My requirements are that logs be correlatable and Kerberos etc work - so milli-second is enough. My Pis have a spread of around 0.002ms ie 2us according to ntpq -p. It doesn't take much to make it far worse. When I update them, I do one at a time per day. Accuracy drops a bit.
I might put in three more at home. ntp needs a lot of sources to converge properly. Ideally five or more. I have quite a decent connection to work.
... reads transcript.
Oh well done - you discovered PTP.
Anyone who actually knows about this stuff like to comment on ntp vs ptp?
Time is hard and the funny thing is - it's relative! Anyone who says they have "solved" time is delusional. The best you can do is reduce errors and problems related to timekeeping to an acceptable level.
I've "solved" time at work with three Raspberry Pis with GPS boards/hats and aerials. My requirements are that logs be correlatable and Kerberos etc work - so milli-second is enough. My Pis have a spread of around 0.002ms ie 2us according to ntpq -p. It doesn't take much to make it far worse. When I update them, I do one at a time per day. Accuracy drops a bit.
I might put in three more at home. ntp needs a lot of sources to converge properly. Ideally five or more. I have quite a decent connection to work.
... reads transcript.
Oh well done - you discovered PTP.
Anyone who actually knows about this stuff like to comment on ntp vs ptp?