Re: [RFC PATCH 0/10] Another Approach to Use PMEM as NUMA Node

From: Michal Hocko
Date: Thu Mar 28 2019 - 02:58:08 EST


On Wed 27-03-19 19:09:10, Yang Shi wrote:
> One question, when doing demote and promote we need define a path, for
> example, DRAM <-> PMEM (assume two tier memory). When determining what nodes
> are "DRAM" nodes, does it make sense to assume the nodes with both cpu and
> memory are DRAM nodes since PMEM nodes are typically cpuless nodes?

Do we really have to special case this for PMEM? Why cannot we simply go
in the zonelist order? In other words why cannot we use the same logic
for a larger NUMA machine and instead of swapping simply fallback to a
less contended NUMA node? It can be a regular DRAM, PMEM or whatever
other type of memory node.
--
Michal Hocko
SUSE Labs