Monitor

https://www.kernel.org/doc/html/latest/admin-guide/numastat.html /sys/devices/system/node/node*/numastat

In more detail:

numa_hit	A process wanted to allocate memory from this node, and succeeded.
numa_miss	A process wanted to allocate memory from another node, but ended up with memory from this node.
numa_foreign	A process wanted to allocate on this node, but ended up with memory from another node.
local_node	A process ran on this node’s CPU, and got memory from this node.
other_node	A process ran on a different node’s CPU and got memory from this node.
interleave_hit	Interleaving wanted to allocate from this node and succeeded.