> The idea that you can ignore the real hardware is particularly unhelpful in Rust, because it's a great fit to low-level problems where the real hardware is a big deal. For example, at work, we have a Rust program where we routinely need to think about NUMA placement and cache coherency protocols. Those don't exist in the Rust abstract machine at all!

If I understand Ralf's overall model here, I think they'd argue that this sort of reasoning must be done within the context of the abstract machine's behavior for std::ptr::{read,write}_volatile, no?