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Comment by leif | Hacker News Reader

FTA: "Assuming servers are kept synchronized enough (the enough depending on your application), you may just solve the problem by acquiring time precisely enough."

How on earth are "sub-microsecond timers" supposed to be synchronized anywhere?

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We have special hardware that syncs our servers to an atomic clock in Colorado. It's about +/- microseconds off. Not sure about sub microsecond tho. Another problem with this is you will run into clock drift and NTP time adjustment bugs. Honestly I stopped reading once he mentioned that time was going to be his secret sauce. There are just too many subtle issues with using that as your globally unique identifier.

If I'm reading the spec sheets correctly, the datacenter rubidium/gps clocks typically used advertise < 5x10^-9 (worst case) to < 5x10^-11 (best case) accuracy.

Which spec sheet? Would like to read more about these.

Something like this:

http://www.spectracomcorp.com/Desktopmodules/Bring2Mind/DMX/...

The units are a bit confusing but the accuracy still translates down to a handful of nanoseconds per month, I believe.

Precision Time Protocol: http://en.m.wikipedia.org/wiki/Precision_Time_Protocol

Or a GPS disciplined clock

OK but the point in the article is to reduce reliance on shared state. This doesn't work in a database.

This is very possible with high quality software, for example, see http://fsmlabs.com

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