On Wed, Jun 03, 2020 at 10:06:31AM +0530, Anshuman Khandual wrote: > Does this look okay and sufficient ? > > --- a/Documentation/vm/page_migration.rst > +++ b/Documentation/vm/page_migration.rst > @@ -253,5 +253,20 @@ which are function pointers of struct address_space_operations. > PG_isolated is alias with PG_reclaim flag so driver shouldn't use the flag > for own purpose. > > +Quantifying Migration > +===================== > +Following events can be used to quantify page migration. > + > +- PGMIGRATE_SUCCESS > +- PGMIGRATE_FAIL > +- THP_MIGRATION_SUCCESS > +- THP_MIGRATION_FAILURE > + > +THP_MIGRATION_FAILURE in particular represents an event when a THP could not be > +migrated as a single entity following an allocation failure and ended up getting > +split into constituent normal pages before being retried. This event, along with > +PGMIGRATE_SUCCESS and PGMIGRATE_FAIL will help in quantifying and analyzing THP > +migration events including both success and failure cases. Looks great! > Sure, will update the commit message accordingly. Thanks. Hopefully these will help someone in the future.
