A UUID is a 128-bit integer. That people do not store, generate, or interact with them that way is the bug.
I'd kill for a 128-bit architecture so a UUID compare would be a single instruction, and it's too bad consensus is that we don't really need it.
Well, there's PCMPESTRI on Intel.
That looks basically like what you need, though, yeah. Cool.
edit: bytes
This perfectly summarizes the bitwise-innumeracy of the argument against UUIDs. Even without 128 bit word sizes, most UUIDs are going to be non-matches in their lower bits, assuming a random distribution. There's no computational efficiency gained in the vastly wide critical path here.
But you can't assume a random distribution because anyone using UUID's for database keys isn't using random UUID's, they're using sequential ones.
I don't believe that's true. You're right that they start the session over, but it'll still be a fresh sequence that doesn't overlap anything generated in the past.
