1 What: /sys/kernel/mm/numa/
3 Contact: Linux memory management mailing list <linux-mm@kvack.org>
4 Description: Interface for NUMA
6 What: /sys/kernel/mm/numa/demotion_enabled
8 Contact: Linux memory management mailing list <linux-mm@kvack.org>
9 Description: Enable/disable demoting pages during reclaim
11 Page migration during reclaim is intended for systems
12 with tiered memory configurations. These systems have
13 multiple types of memory with varied performance
14 characteristics instead of plain NUMA systems where
15 the same kind of memory is found at varied distances.
16 Allowing page migration during reclaim enables these
17 systems to migrate pages from fast tiers to slow tiers
18 when the fast tier is under pressure. This migration
19 is performed before swap. It may move data to a NUMA
20 node that does not fall into the cpuset of the
21 allocating process which might be construed to violate
22 the guarantees of cpusets. This should not be enabled
23 on systems which need strict cpuset location