Thank you Dr. Kleppmann, you really make me get more interested in learning Distributed Systems. I've already bought your published book to study and learn more!
6:30 the total network delay can be found by looking at time stamps but this assumes network symmetry We can estimate what t4 was supposed to be and compare with actual. The estimate is t3+(delta/2). Difference between actual t4 and expected is the clock skew
@Martin, thanks for sharing. I'm new to this subject and trying to understand how to convert Time Error (drift in seconds per day) to precision in positioning. There are claims suggesting TE at 10^(-18) provides cm precision. If we multiply 10^(-18)*86400 (sec/day)*speed of light, the precision should sub cm. I would be grateful if you help with a comment or reference. Many thanks.
I am thinking resetting the client clock happens if the skew is larger instead of slewing as in smaller skew case is because synchronizing the clocks would take a long time otherwise.
I can't understand the slew chart at 10:06. If the clock ended being synchronized at ~200th mark (miilisecond?) itself, why was the quartz still ticking slowly until ~650 ms?
In NTP why can you do (t4 - t1) - (t3 - t2) ? First two terms are from the client and second two terms are from the server, and if the two clocks have different rates than aren't you working with different units? Or is the assumption that the rates are 'close enough', i.e. corrections to the corrections are second-order?
What an amazing videos!! Thanks so much! I learn more in a 15-minute than my entire semester.
what did u do in ur entire semester then。。。
@@Yaomuuuuu he's sleeping or being absent
Thanks Dr. Kleppmann for the amazing series of lectures.
Thank you Dr. Kleppmann, you really make me get more interested in learning Distributed Systems. I've already bought your published book to study and learn more!
This was extremely helpful and comprehensive. Thank you so much!
6:30 the total network delay can be found by looking at time stamps but this assumes network symmetry
We can estimate what t4 was supposed to be and compare with actual. The estimate is t3+(delta/2). Difference between actual t4 and expected is the clock skew
Thank you. NTP implementation was always like latin to me. But, i understand it much clearly now.
u are the GOAT of DS!
Python: time.monotonic() to replace time.time()
Thanks. I was wondering what the equivalent would be in Python
time.monotonic_ns() → int
Similar to monotonic(), but return time as nanoseconds.
New in version 3.7.
The frequency graph blew my mind. Wow.
so interesting! thank you so much for posting this series : )
Great work.
@Martin, thanks for sharing. I'm new to this subject and trying to understand how to convert Time Error (drift in seconds per day) to precision in positioning. There are claims suggesting TE at 10^(-18) provides cm precision. If we multiply 10^(-18)*86400 (sec/day)*speed of light, the precision should sub cm. I would be grateful if you help with a comment or reference. Many thanks.
Love it, thanks for sharing!
I am thinking resetting the client clock happens if the skew is larger instead of slewing as in smaller skew case is because synchronizing the clocks would take a long time otherwise.
Thanks a lot for this video
I can't understand the slew chart at 10:06. If the clock ended being synchronized at ~200th mark (miilisecond?) itself, why was the quartz still ticking slowly until ~650 ms?
Thanks bro you legend
In NTP why can you do (t4 - t1) - (t3 - t2) ? First two terms are from the client and second two terms are from the server, and if the two clocks have different rates than aren't you working with different units? Or is the assumption that the rates are 'close enough', i.e. corrections to the corrections are second-order?
Monotonic clocks are not affected by steps. But are they affected by slews?
is the ntp used to sync the time for different timezone or in local network, because I see it accepts up to 1000s which is almost 30 minutes
NTP has no concept of timezone, it's always UTC. The timezone is applied after sync
🙏🌹🙏
icons are watching this video day before day exams
I need java source code for Clock syncronization