On Wed 11-04-18 17:09:25, Naoya Horiguchi wrote: > Hi everyone, > > I wrote patches introducing separate vm event counters for hugepage migration > (both for hugetlb and thp.) > Hugepage migration is different from normal page migration in event frequency > and/or how likely it succeeds, so maintaining statistics for them in mixed > counters might not be helpful both for develors and users.
This is quite a lot of code to be added se we should better document what it is intended for. Sure I understand your reasonaning about huge pages are more likely to fail but is this really worth a separate counter? Do you have an example of how this would be useful? If we are there then what about different huge page sizes (for hugetlb)? Do we need per-hstate stats? In other words, is this really worth it? > include/linux/vm_event_item.h | 7 +++ > mm/migrate.c | 103 > +++++++++++++++++++++++++++++++++++------- > mm/vmstat.c | 8 ++++ > 3 files changed, 102 insertions(+), 16 deletions(-) -- Michal Hocko SUSE Labs