I am trying to find out how Numa balance/weighs per host is taking care of in Nova.

I know how weighers work in general, but it's weighing between hosts. I am not so clear when it comes to a single host with multiple sockets, how does nova weigh them?

For instance, a host has 4 sockets, A, B, C, D. When scheduling request comes in asking for 4 cores on 2 sockets(2 cores per socket), scheduler realized that A+B, A+C, and C+D combination can all fit the request. In this case, how does nova make the decision on which combination to choose from?

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