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Comment by billforsternz | Hacker News Reader

My intuition is that occasional software crashes like this probably follow a Poisson distribution statistically speaking. Like occasional cars appearing on a lonely street. One car appearing doesn't affect the expected arrival of the next car. So rebooting before the start of a mission is not an effective strategy. Just idle speculation based on a stats and probability class 36 years ago. Happy to be proven wrong.

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Unless the crashes are caused by things cosmic rays, they're very likely influenced by the internal state of the aircraft and therefor not independent events. If that car showing up causes the world to reset - then you won't likely see another car for a few million years.

I somewhat doubt that model is valid for these issues. A large number of software issues relate to run time of a system. In particular, this one seems to be clock drift from other comments. That's more of a random walk; which crashes a system at some given distance.

If I read the thing right, the system is in sync at reboot and effectively, jitter renders it unstable over time. So events are not independent.

When you start a mission you are literally starting up the plane. Along the way you turn on the avionics, authenticate, turn on the engine, ask the plane to perform a comprehensive set of built in tests, etc. You are booting up. It does not make sense to reboot before you've even booted up in the first place.

In general I would agree.

But there could be indeed some SW failures that are more likely after a given time of running. E.g. memory [de]allocation problems, memory fragmentation - in case the use some kind of dynamic memory. Or other types of resource leaks.

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