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by lmm 6 days ago
Most hardware has an exponential (memoryless) failure distribution in practice. The bathtub curve is a myth.
2 comments
fc417fc802 6 days ago
A bathtub curve is also memoryless though, and the back portion can be exponential. Consider two sub-populations of the same hardware. The first is small, evaded QA, and will fail early. Failures follow an exponential fall off. The second is much larger and failures rise exponentially with age.

Also consider mixing in "was dropped during shipping" or "was stored improperly".

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eru 6 days ago
How is a bathtub curve memoryless?
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fc417fc802 5 days ago
My mistake, it seems I misunderstood what OP meant by that. Ignore that semantic detail and my position still stands. You've got a mix of subpopulations and many of the failure modes are definitely time dependent in some manner at least in the real world.
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eru 5 days ago
No worries. I just thought I was misunderstanding something.
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Xalutiono 6 days ago
Where is this exponential thing coming from?

Why would hardware failure raise exponential with linear scale? Doesn't make sense

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eru 6 days ago
> Where is this exponential thing coming from?

That's what you get from a constant failure rate per unit of time.

It's saying that hardware fails in the same way that Carbon-14 dating works.

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Xalutiono 5 days ago
Lets hope they add more context to it.

Most if not all hardware failure on my side is def not memoryless besides the one lightning damage thingy but thats not hardwares fault.

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lmm 5 days ago
https://en.wikipedia.org/wiki/Memorylessness
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