On Wed, 21 Feb 2024 09:44:32 +0800 Bixuan Cui <cuibixuan@xxxxxxxx> wrote: > ping~ > It's up to the memory management folks to decide on this. -- Steve > 在 2024/1/5 9:36, Bixuan Cui 写道: > > When the system memory is low, kswapd reclaims the memory. The key steps > > of memory reclamation include > > 1.shrink_lruvec > > * shrink_active_list, moves folios from the active LRU to the inactive LRU > > * shrink_inactive_list, shrink lru from inactive LRU list > > 2.shrink_slab > > * shrinker->count_objects(), calculates the freeable memory > > * shrinker->scan_objects(), reclaims the slab memory > > > > The existing tracers in the vmscan are as follows: > > > > --do_try_to_free_pages > > --shrink_zones > > --trace_mm_vmscan_node_reclaim_begin (tracer) > > --shrink_node > > --shrink_node_memcgs > > --trace_mm_vmscan_memcg_shrink_begin (tracer) > > --shrink_lruvec > > --shrink_list > > --shrink_active_list > > --trace_mm_vmscan_lru_shrink_active (tracer) > > --shrink_inactive_list > > --trace_mm_vmscan_lru_shrink_inactive (tracer) > > --shrink_active_list > > --shrink_slab > > --do_shrink_slab > > --shrinker->count_objects() > > --trace_mm_shrink_slab_start (tracer) > > --shrinker->scan_objects() > > --trace_mm_shrink_slab_end (tracer) > > --trace_mm_vmscan_memcg_shrink_end (tracer) > > --trace_mm_vmscan_node_reclaim_end (tracer) > > > > If we get the duration and quantity of shrink lru and slab, > > then we can measure the memory recycling, as follows > > > > Measuring memory reclamation with bpf: > > LRU FILE: > > CPU COMM ShrinkActive(us) ShrinkInactive(us) Reclaim(page) > > 7 kswapd0 26 51 32 > > 7 kswapd0 52 47 13 > > SLAB: > > CPU COMM OBJ_NAME Count_Dur(us) Freeable(page) Scan_Dur(us) Reclaim(page) > > 1 kswapd0 super_cache_scan.cfi_jt 2 341 3225 128 > > 7 kswapd0 super_cache_scan.cfi_jt 0 2247 8524 1024 > > 7 kswapd0 super_cache_scan.cfi_jt 2367 0 0 0 > > > > For this, add the new tracer to shrink_active_list/shrink_inactive_list > > and shrinker->count_objects(). > > > > Changes: > > v6: * Add Reviewed-by from Steven Rostedt. > > v5: * Use 'DECLARE_EVENT_CLASS(mm_vmscan_lru_shrink_start_template' to > > replace 'RACE_EVENT(mm_vmscan_lru_shrink_inactive/active_start' > > * Add the explanation for adding new shrink lru events into 'mm: vmscan: add new event to trace shrink lru' > > v4: Add Reviewed-by and Changlog to every patch. > > v3: Swap the positions of 'nid' and 'freeable' to prevent the hole in the trace event. > > v2: Modify trace_mm_vmscan_lru_shrink_inactive() in evict_folios() at the same time to fix build error. > > > > cuibixuan (2): > > mm: shrinker: add new event to trace shrink count > > mm: vmscan: add new event to trace shrink lru > > > > include/trace/events/vmscan.h | 80 ++++++++++++++++++++++++++++++++++- > > mm/shrinker.c | 4 ++ > > mm/vmscan.c | 11 +++-- > > 3 files changed, 90 insertions(+), 5 deletions(-) > >
