On Mon, Feb 17, 2020 at 09:41:40PM -0800, David Rientjes wrote: > The thp_fault_fallback stat in either /proc/vmstat is incremented if > either the hugepage allocation fails through the page allocator or the > hugepage charge fails through mem cgroup. > > This patch leaves this field untouched but adds a new field, > thp_fault_fallback_charge, which is incremented only when the mem cgroup > charge fails. > > This distinguishes between faults that want to be backed by hugepages but > fail due to fragmentation (or low memory conditions) and those that fail > due to mem cgroup limits. That can be used to determine the impact of > fragmentation on the system by excluding faults that failed due to memcg > usage. > > Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx> The patch looks good to me, but I noticed that we miss THP_FAULT_FALLBACK (and THP_FAULT_FALLBACK_CHARGE) accounting in shmem_getpage_gfp(). Could you fix this while you are there? -- Kirill A. Shutemov
