On 2/12/26 7:24 AM, Vlastimil Babka wrote:
On 2/12/26 05:51, JP Kobryn wrote:
It would be useful to see a breakdown of allocations to understand which
NUMA policies are driving them. For example, when investigating memory
pressure, having policy-specific counts could show that allocations were
bound to the affected node (via MPOL_BIND).
Add per-policy page allocation counters as new node stat items. These
counters can provide correlation between a mempolicy and pressure on a
given node.
Signed-off-by: JP Kobryn <[email protected]>
Suggested-by: Johannes Weiner <[email protected]>
Are the numa_{hit,miss,etc.} counters insufficient? Could they be extended
in a way that would capture any missing important details? A counter per
policy type seems exhaustive, but then on one hand it might be not important
to distinguish beetween some of them, and on the other hand it doesn't track
the nodemask anyway.
The two patches of the series should complement each other. When
investigating memory pressure, we could identify the affected nodes
(patch 2). Then we can cross-reference the policy-specific stats to find
any correlation (this patch).
I think extending numa_* counters would call for more permutations to
account for the numa stat per policy. I think distinguishing between
MPOL_DEFAULT and MPOL_BIND is meaningful, for example. Am I
understanding your question?
