I was looking at one of my favorite works of art recently and realized that it reminds me a lot of the concept of time in distributed systems. The melting clocks are a great illustration for the fact that the notion of time as we understand it makes little sense in a distributed system where each node has its own physical clock that runs independently of the other clocks. In a single node system one can look at timestamps to figure out the ordering of events. However, this concept breaks down for a multi-node system involving multiple clocks due to problems like clock skew. While several types of logical clocks have been created to solve this problem and help come up with causal ordering between events I think it is fascinating that time, something we pretty much take for granted everyday, is something you cannot rely on anymore in a distributed system. This was one of the first problems I was exposed to while studying distributed systems and understanding how one can solve it was extremely intellectually satisfying.
Aside – in the past few years I’ve discovered that I’m a fan of surreal art. Another artist I quite like is Rene Magritte, with The Son of Man, The Human Condition, and The Treachery of Images being my favorite works by him.