Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> writes: > Hi, > > Currently, on our ARM servers with NUMA enabled, we found the cross-die latency > is a little larger that will significantly impact the workload's performance. > So on ARM servers we will rely on the NUMA balancing to avoid the cross-die > accessing. And I posted a patchset[1] to support speculative numa fault to > improve the NUMA balancing's performance according to the principle of data > locality. Moreover, thanks to Huang Ying's patchset[2], which introduced batch > migration as a way to reduce the cost of TLB flush, and it will also benefit > the migration of multiple pages all at once during NUMA balancing. > > So we plan to continue to support batch migration in do_numa_page() to improve > the NUMA balancing's performance, but before adding complicated batch migration > algorithm for NUMA balancing, some cleanup and preparation work need to do firstly, > which are done in this patch set. In short, this patchset extends the > migrate_misplaced_page() interface to support batch migration, and no functional > changes intended. Will these cleanup benefit anything except batching migration? If not, I suggest you to post the whole series. In this way, people will be more clear about why we need these cleanup. -- Best Regards, Huang, Ying > [1] https://lore.kernel.org/lkml/cover.1639306956.git.baolin.wang@xxxxxxxxxxxxxxxxx/t/#mc45929849b5d0e29b5fdd9d50425f8e95b8f2563 > [2] https://lore.kernel.org/all/20230213123444.155149-1-ying.huang@xxxxxxxxx/T/#u > > Baolin Wang (4): > mm: migrate: move migration validation into numa_migrate_prep() > mm: migrate: move the numamigrate_isolate_page() into do_numa_page() > mm: migrate: change migrate_misplaced_page() to support multiple pages > migration > mm: migrate: change to return the number of pages migrated > successfully > > include/linux/migrate.h | 15 ++++++++--- > mm/huge_memory.c | 19 +++++++++++--- > mm/memory.c | 34 +++++++++++++++++++++++- > mm/migrate.c | 58 ++++++++--------------------------------- > 4 files changed, 71 insertions(+), 55 deletions(-)
