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If the latter, I don't think we need per-CPU page tables > to do it. In a sense both, if you build a system with poor cross-socket performance then there can be big wins to replicate .text. I've thought kernel needs to do it with text replication, there are too many absolute relocations to make two .text VAs work? Userspace can meaningfully work on a non-replicated basis where single processes are localized to sockets. I think people do things like this already, but AFAIK it is not ergonomic to setup. Jason