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Comment by jemmyw | Hacker News Reader

Software doesn't operate in some magical realm outside of the physical world. It very much is constrained by real world limitations. It runs on the hardware that itself is limited. I wonder if some failures are a result of thinking it doesn't have these limitations?

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As the great Joe Armstrong used to say, “a lot of systems actually break the laws of physics”[1] — don’t program against the laws of physics.

> In distributed systems there is no real shared state (imagine one machine in the USA another in Sweden) where is the shared state? In the middle of the Atlantic? - shared state breaks laws of physics. State changes are propagated at the speed of light - we always know how things were at a remote site not how they are now. What we know is what they last told us. If you make a software abstraction that ignores this fact you’ll be in trouble.[2]

[1]: “The Mess We’re In”, 2014 https://www.youtube.com/watch?v=lKXe3HUG2l4

[2]: https://news.ycombinator.com/item?id=19708900

> It very much is constrained by real world limitations. It runs on the hardware that itself is limited

And yet we scale the shit out of it, shifting limitations further and further. On that scale different problems emerge and there is no single person or even single team that could comprehend this complexity in isolation. You start to encounter problems that have never been solved before.

You can scale it within the bounds of the physical hardware it is running on. And as you scale it you start running into all the problems brought about by distributed systems, problems which very much stem from physics.

Except that it kind of does. I can horizontally scale a distributed storage system until we run out of silicon. I cannot do the same with a cargo airplane.

I'm puzzled by your reply because it starts out by refuting that software is constrained by physics "Except it kind of does" and then immediately gives an example of it being constrained by physics "until we run out of silicon".

You can horizontally scale cargo transport by running more cargo planes until you're constrained in some way.

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