[jhayward]

Thanks, this is a helpful introduction to the history and literature of concepts related to time in distributed systems. Most people's concept of time is quite simple and they need to be broken loose of some intuitively held, but unhelpful beliefs before they can really do engineering with respect to time.

Is there a paper somewhere that new folk should read first? One that includes:

- A tutorial to describe all of the things we think of as 'time', e.g. order of sequence, etc. and their dependence on each other.

- The idea that time as it occurs in the physical world is probabilistic - requiring such descriptors as precision (what is the smallest difference we can discern), and error bounds or probability distributions (how accurately can we describe it).

- And for the concrete thinkers who 'get' that true simultaneity is impossible, an easy to understand example of how we succeed in observing logical coherence, from the scale of a single CPU chip (internally non-coherent, externally consistent) to cross-continent compute clusters?

[nuxi]

There was a great presentation given by Tom Van Baak on measuring time, precision, accuracy etc. at this year's FOSDEM . Abstract an video are available at https://fosdem.org/2015/schedule/event/precise_time/, he has lots of additional time-related information on his website http://leapsecond.com/.