Comment by mlyle

> you're trusting software developers either way, whether it be at the app level, the language/runtime level, or the operating system level.

I trust systems to do better based on observed behavior rather than a software engineer's guess of how it will be scheduled. Who knows if, in a given use case, the program is a "small" part of the system or a "large" part that should get preferential placement and scheduling.

> If a threadpool manager is hinted that 4 threads are going to share a lot of memory, they can be allocated on the same l2 cache.

And so this is kind of a weird thing: we know we're going to be performance critical and we need things to be forced to be adjacent... but we don't know the exact details of the hardware we're running on. (Else, just numa_bind and be done...)