4 ms·
> What do you need this accurate time for? Some major uses of high-precision timing, albeit not with NTP, include: * Synchronising cell phone towers, the syst
by michaelt 1y ago
> What do you need this accurate time for?
Some major uses of high-precision timing, albeit not with NTP, include:
* Synchronising cell phone towers, the system partly relies on precise timing to avoid them interfering with one another.
* Timestamping required by regulators, in industries like high-frequency trading.
* Certain video production systems, where a ten-parts-per-million framerate error would build up into an unacceptable 1.7 second error over 48 hours.
* Certain databases (most famously Google Spanner) that use precise timing to ensure events are ordered correctly
* As a debugging luxury in distributed systems.
In some of these applications you could get away with a precise-but-free-floating time, as you only need things precisely synchronised relative to one another, not globally. But if you're building an entire data centre, a sub-$1000 GPS-controlled clock is barely noticeable.
- rkomorn 1y ago> But if you're building an entire data centre, a sub-$1000 GPS-controlled clock is barely noticeable. Dumb personal and useless anecdote: one of those appliances made my life more difficult for months (at a FAANG company that built its own data centers, no less) for the nearly comical reason that we needed to move it but somehow couldn't rewire the GPS antenna, and the delays kept retriggering alerting that we kept disabling until the expecte "it'll be moved by then" time. So, I guess to make the anecdote more useful: if you're gonna get one, make sure it doesn't hamstring you with wires...
- michaelt 1y agoThe secret, I'm told, is to make friends with the CCTV/access control team. They always know the paperwork and contractors needed to get a guy on a cherrypicker drilling holes and installing data cables without upsetting the building owners.