diff options
| author | Mel Gorman <[email protected]> | 2016-07-28 15:46:59 -0700 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2016-07-28 16:07:41 -0700 |
| commit | 7cc30fcfd2a894589d832a192cac3dc5cd302bb8 (patch) | |
| tree | 5f32cf9ee52f5bd6e003853507fdb031b1d1124c /include/linux | |
| parent | 16709d1de1954475356a65848f80a01581b4903c (diff) | |
mm: vmstat: account per-zone stalls and pages skipped during reclaim
The vmstat allocstall was fairly useful in the general sense but
node-based LRUs change that. It's important to know if a stall was for
an address-limited allocation request as this will require skipping
pages from other zones. This patch adds pgstall_* counters to replace
allocstall. The sum of the counters will equal the old allocstall so it
can be trivially recalculated. A high number of address-limited
allocation requests may result in a lot of useless LRU scanning for
suitable pages.
As address-limited allocations require pages to be skipped, it's
important to know how much useless LRU scanning took place so this patch
adds pgskip* counters. This yields the following model
1. The number of address-space limited stalls can be accounted for (pgstall)
2. The amount of useless work required to reclaim the data is accounted (pgskip)
3. The total number of scans is available from pgscan_kswapd and pgscan_direct
so from that the ratio of useful to useless scans can be calculated.
[[email protected]: s/pgstall/allocstall/]
Link: http://lkml.kernel.org/r/[email protected]: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Mel Gorman <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Hillf Danton <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Cc: Joonsoo Kim <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Minchan Kim <[email protected]>
Cc: Rik van Riel <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/vm_event_item.h | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h index 1798ff542517..4d6ec58a8d45 100644 --- a/include/linux/vm_event_item.h +++ b/include/linux/vm_event_item.h @@ -23,6 +23,8 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, FOR_ALL_ZONES(PGALLOC), + FOR_ALL_ZONES(ALLOCSTALL), + FOR_ALL_ZONES(PGSCAN_SKIP), PGFREE, PGACTIVATE, PGDEACTIVATE, PGFAULT, PGMAJFAULT, PGLAZYFREED, @@ -37,7 +39,7 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT, #endif PGINODESTEAL, SLABS_SCANNED, KSWAPD_INODESTEAL, KSWAPD_LOW_WMARK_HIT_QUICKLY, KSWAPD_HIGH_WMARK_HIT_QUICKLY, - PAGEOUTRUN, ALLOCSTALL, PGROTATED, + PAGEOUTRUN, PGROTATED, DROP_PAGECACHE, DROP_SLAB, #ifdef CONFIG_NUMA_BALANCING NUMA_PTE_UPDATES, |