Comment by menaerus

> But why aren’t LLM inference engines deterministic? One common hypothesis is that some combination of floating-point non-associativity and concurrent execution leads to nondeterminism based on which concurrent core finishes first. We will call this the “concurrency + floating point” hypothesis for LLM inference nondeterminism. For example, a recent arXiv preprint writes

I'm honored to see that Mira and co. appreciated my feedback on the very topic I made 7 months ago here :D

> You don't need RNG since the whole transformer is an extremely large floating-point arithmetic unit. A wild guess - how about the source of non-determinism is coming from the fact that, on the HW level, tensor execution order is not guaranteed and therefore (T0 * T1) * T2 can produce slightly different results than T0 * (T1 * T2) due to rounding errors?

https://news.ycombinator.com/item?id=42952605#42960047