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I believe that is what my patch is fixing. If >> previous CPU and current CPU share cache, we prefer busy cores with free >> previous idle SMT, otherwise go looking for fully idle cores. But it sounds like >> from Peter's reply that is not necessarily a good thing to do in case 'fast >> numa'. So I guess there is no good answer (?) or way of doing it. > > Yeah, recent AMD CPUs can be configured into NUMA mode where each chiplet is > reported as a node and they do behave like one as each has its own memory > connection but the distances among them are significantly closer than > traditional multi-socket. That said, I think the implementation is still a > bit too happy to jump the boundary. What Andrea is suggesting seems > reasonable? > Thanks for sharing the AMD configurations. Yeah, agreed on Andrea's suggestion. - Joel