Clock Precision and Synchronization

The cluster discusses challenges in achieving high-precision clock accuracy, synchronization, drift, slew, and timing in hardware like CPUs, motherboards, and systems, including use cases, limitations, and comparisons to techniques like NTP or atomic clocks.

➡️ Stable 0.6x Hardware
3,335
Comments
20
Years Active
5
Top Authors
#9279
Topic ID

Activity Over Time

2007
1
2008
5
2009
12
2010
30
2011
43
2012
60
2013
95
2014
155
2015
121
2016
166
2017
208
2018
292
2019
187
2020
251
2021
333
2022
309
2023
361
2024
295
2025
394
2026
17

Keywords

HAQ II CPU e.g PC HDL RPC UNIX RF CAD clock clocks accurate timing sync temperature frequency gps signal network

Sample Comments

abwizz Jun 23, 2023 View on HN

feels like the requirements of precision over time (clockdrift) put limits on the usefulness of this method

cma Sep 11, 2019 View on HN

This doesn't give more timing precision than previous techniques?

adolph Jun 23, 2023 View on HN

How long does it take to get clocks synchronized within a few nanoseconds?

adastra22 Mar 2, 2023 View on HN

Clock slew is unacceptable for many use cases. For keeping system time on a UNIX server or for astronaut watches, sure. For many other things you need a precise and accurate count of how many micro/nano/pico seconds have passed. You can’t just have one second suddenly be N nanoseconds longer and expect sensitive experiments to not be affected.

hinkley Aug 10, 2025 View on HN

So the clock skew is high resolution but the clock rate is low. Makes sense.

skykooler Aug 27, 2018 View on HN

What is the use case for microsecond-accurate timekeeping?

nickpeterson Mar 9, 2017 View on HN

I'm struck by how hard it would be to track down a bug that depends on the consistency of the clockrate...

philjohn Oct 3, 2019 View on HN

You run the risk of the computational equivalent of speedo not beeing 100% accurate, e.g. clock innacuracy.

jcelerier Aug 21, 2017 View on HN

on recent good hardware there is no problem being around 1ms accuracy.

koffiezet Mar 9, 2017 View on HN

Bugs like the ones you describe come down to timing.But it's not like "the old days" where for a specific target, there was only 1 chip/clockspeed so devs simply relied on it for timing since an RTC was or not available, or too slow to access.These days, it would be very hard to actually write code that relies on a specific clock-rate and work reliably. It's a lot easier and reliable to use the clock for time-sensitive stuff.