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66 days + 12 hours are 5,745,600,000,000,000 ns. The log2 of this is 52.351...

Javascript and some other languages only have integer precision up to 52 bits then they switch to floating point.

Curious.

Bingo! Someone decided to store timestamps in float64 which has 52 bit mantissa, and the time functions break when losing precision.

It's 32 bits of milliseconds, right? Hm, no, that would overflow much sooner (49.7 days).

It's a uint32_t of 750 Hz "jiffies", which does overflow at ~66 days.

While that seems like a convincing explanation, 750Hz is a rather odd value to use for a timer, and more importantly the overflow would be at 66d6h43m43s instead of the reported ~66d12h.

66 days 12 hours would put it at 747.5 Hz. A different report had 66 days 10 hours 16 minutes which works out to 748 Hz.

Maybe the clock was just feeling a little sluggish? /s

It is indeed the explanation: https://github.com/NVIDIA/open-gpu-kernel-modules/pull/1014

Wild.

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