On 1/28/24 22:22, Artem Kuzin wrote:

As for possible options, for now I am thinking about two:
1. additional config option to limit the number of page tables and corresponding replicas

This doesn't help.  Everybody runs distro kernels with the same configs
with MAX_NUMNODES set to 1024.

2. setup per-NUMA node page tables and replicas in a lazy way allocating them on demand

... and probably shrinking them on demand too (or at least limiting
their growth).  You don't want to have a random long-lived process
that's migrated to 50 different nodes having 50 different PGD pages when
it can only use one at a time.