On Wed 02-03-16 13:24:10, Michal Hocko wrote:
> On Tue 01-03-16 19:14:08, Vlastimil Babka wrote:
[...]
> > I would suggest enabling all compaction tracepoint and the migration
> > tracepoint. Looking at the trace could hopefully help faster than
> > going one trace_printk() per attempt.
>
> OK, here we go with both watermarks checks removed and hopefully all the
> compaction related tracepoints enabled:
> echo 1 > /debug/tracing/events/compaction/enable
> echo 1 > /debug/tracing/events/migrate/mm_migrate_pages/enable
>
> this was without the hugetlb handicap. See the trace log and vmstat
> after the run attached.
Just for the reference the above was with:
diff --git a/mm/compaction.c b/mm/compaction.c
index 4d99e1f5055c..7364e48cf69a 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -1276,6 +1276,9 @@ static unsigned long __compaction_suitable(struct zone *zone, int order,
alloc_flags))
return COMPACT_PARTIAL;
+ if (order <= PAGE_ALLOC_COSTLY_ORDER)
+ return COMPACT_CONTINUE;
+
/*
* Watermarks for order-0 must be met for compaction. Note the 2UL.
* This is because during migration, copies of pages need to be
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 1993894b4219..50954a9a4433 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2245,7 +2245,6 @@ EXPORT_SYMBOL_GPL(split_page);
int __isolate_free_page(struct page *page, unsigned int order)
{
- unsigned long watermark;
struct zone *zone;
int mt;
@@ -2254,14 +2253,8 @@ int __isolate_free_page(struct page *page, unsigned int order)
zone = page_zone(page);
mt = get_pageblock_migratetype(page);
- if (!is_migrate_isolate(mt)) {
- /* Obey watermarks as if the page was being allocated */
- watermark = low_wmark_pages(zone) + (1 << order);
- if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
- return 0;
-
+ if (!is_migrate_isolate(mt))
__mod_zone_freepage_state(zone, -(1UL << order), mt);
- }
/* Remove page from free list */
list_del(&page->lru);
And I rerun the same with the clean mmotm tree and the results are
attached.
As we can see there was less scanning on dma32 both in direct and kswapd
reclaim.
$ grep direct vmstat.*
vmstat.mmotm.log:pgsteal_direct_dma 420
vmstat.mmotm.log:pgsteal_direct_dma32 71234
vmstat.mmotm.log:pgsteal_direct_normal 0
vmstat.mmotm.log:pgsteal_direct_movable 0
vmstat.mmotm.log:pgscan_direct_dma 990
vmstat.mmotm.log:pgscan_direct_dma32 144376
vmstat.mmotm.log:pgscan_direct_normal 0
vmstat.mmotm.log:pgscan_direct_movable 0
vmstat.mmotm.log:pgscan_direct_throttle 0
vmstat.updated.log:pgsteal_direct_dma 334
vmstat.updated.log:pgsteal_direct_dma32 71877
vmstat.updated.log:pgsteal_direct_normal 0
vmstat.updated.log:pgsteal_direct_movable 0
vmstat.updated.log:pgscan_direct_dma 670
vmstat.updated.log:pgscan_direct_dma32 137488
vmstat.updated.log:pgscan_direct_normal 0
vmstat.updated.log:pgscan_direct_movable 0
vmstat.updated.log:pgscan_direct_throttle 0
$ grep kswapd vmstat.*
vmstat.mmotm.log:pgsteal_kswapd_dma 5602
vmstat.mmotm.log:pgsteal_kswapd_dma32 332336
vmstat.mmotm.log:pgsteal_kswapd_normal 0
vmstat.mmotm.log:pgsteal_kswapd_movable 0
vmstat.mmotm.log:pgscan_kswapd_dma 12187
vmstat.mmotm.log:pgscan_kswapd_dma32 679667
vmstat.mmotm.log:pgscan_kswapd_normal 0
vmstat.mmotm.log:pgscan_kswapd_movable 0
vmstat.mmotm.log:kswapd_inodesteal 0
vmstat.mmotm.log:kswapd_low_wmark_hit_quickly 339
vmstat.mmotm.log:kswapd_high_wmark_hit_quickly 10
vmstat.updated.log:pgsteal_kswapd_dma 5339
vmstat.updated.log:pgsteal_kswapd_dma32 322951
vmstat.updated.log:pgsteal_kswapd_normal 0
vmstat.updated.log:pgsteal_kswapd_movable 0
vmstat.updated.log:pgscan_kswapd_dma 11213
vmstat.updated.log:pgscan_kswapd_dma32 653096
vmstat.updated.log:pgscan_kswapd_normal 0
vmstat.updated.log:pgscan_kswapd_movable 0
vmstat.updated.log:kswapd_inodesteal 0
vmstat.updated.log:kswapd_low_wmark_hit_quickly 351
vmstat.updated.log:kswapd_high_wmark_hit_quickly 13
--
Michal Hocko
SUSE Labs
Attachment:
trace.mmotm.log.gz
Description: application/gzip
nr_free_pages 149226 nr_alloc_batch 114 nr_inactive_anon 13962 nr_active_anon 46754 nr_inactive_file 634 nr_active_file 5010 nr_unevictable 0 nr_mlock 0 nr_anon_pages 219 nr_mapped 793 nr_file_pages 66233 nr_dirty 0 nr_writeback 0 nr_slab_reclaimable 12355 nr_slab_unreclaimable 21208 nr_page_table_pages 320 nr_kernel_stack 92 nr_unstable 0 nr_bounce 0 nr_vmscan_write 358705 nr_vmscan_immediate_reclaim 111 nr_writeback_temp 0 nr_isolated_anon 0 nr_isolated_file 0 nr_shmem 58505 nr_dirtied 5516 nr_written 360677 nr_pages_scanned 0 workingset_refault 17291 workingset_activate 11908 workingset_nodereclaim 644 nr_anon_transparent_hugepages 0 nr_free_cma 0 nr_dirty_threshold 30487 nr_dirty_background_threshold 15243 pgpgin 525267 pgpgout 1444464 pswpin 75386 pswpout 358705 pgalloc_dma 241466 pgalloc_dma32 21491760 pgalloc_normal 0 pgalloc_movable 0 pgfree 22110844 pgactivate 204005 pgdeactivate 1033621 pgfault 23929641 pgmajfault 27748 pglazyfreed 0 pgrefill_dma 18759 pgrefill_dma32 1122090 pgrefill_normal 0 pgrefill_movable 0 pgsteal_kswapd_dma 5602 pgsteal_kswapd_dma32 332336 pgsteal_kswapd_normal 0 pgsteal_kswapd_movable 0 pgsteal_direct_dma 420 pgsteal_direct_dma32 71234 pgsteal_direct_normal 0 pgsteal_direct_movable 0 pgscan_kswapd_dma 12187 pgscan_kswapd_dma32 679667 pgscan_kswapd_normal 0 pgscan_kswapd_movable 0 pgscan_direct_dma 990 pgscan_direct_dma32 144376 pgscan_direct_normal 0 pgscan_direct_movable 0 pgscan_direct_throttle 0 pginodesteal 0 slabs_scanned 2052 kswapd_inodesteal 0 kswapd_low_wmark_hit_quickly 339 kswapd_high_wmark_hit_quickly 10 pageoutrun 448 allocstall 1376 pgrotated 357091 drop_pagecache 0 drop_slab 0 pgmigrate_success 227102 pgmigrate_fail 142 compact_migrate_scanned 374515 compact_free_scanned 4000566 compact_isolated 456131 compact_stall 133 compact_fail 73 compact_success 60 compact_kcompatd_wake 0 htlb_buddy_alloc_success 0 htlb_buddy_alloc_fail 0 unevictable_pgs_culled 1087 unevictable_pgs_scanned 0 unevictable_pgs_rescued 1530 unevictable_pgs_mlocked 1530 unevictable_pgs_munlocked 1529 unevictable_pgs_cleared 1 unevictable_pgs_stranded 0 thp_fault_alloc 164 thp_fault_fallback 26 thp_collapse_alloc 159 thp_collapse_alloc_failed 11 thp_split_page 0 thp_split_page_failed 0 thp_deferred_split_page 309 thp_split_pmd 7 thp_zero_page_alloc 3 thp_zero_page_alloc_failed 0