The commit is pushed to "branch-rh7-3.10.0-957.10.1.vz7.85.x-ovz" and will
appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-957.10.1.vz7.85.7
------>
commit d742225d792a285e92ea982b8e0d9511f87ddc44
Author: Andrey Ryabinin <[email protected]>
Date: Fri Mar 29 16:44:42 2019 +0300
mm/vmscan: scan active file and anon lists if inactive file list is too
short
ltp test mm.mtest01w fails: it just tries to allocate and use 80% of
available RAM+swap which is > RAMSIZE, so swap is intended to be used.
Instead the test process is killed by OOM:
get_scan_count() detects that cgroup has enough inactive file to reclaim
only it and does not touch active anon.
(inactive_file_low == false, as the test does not generate pagecache at
all and there are several entries in inactive pagecache (1-10) which we
cann't reclaim, they are activated instead).
Thus active lists are not reclaimed => active anon (plenty of it) is not
reclaimed (swapped out), reclaim is unsuccessful => OOM.
How we fix this:
1) we honor absolute value of inactive file cache:
scan_balance is set to SCAN_FILE only in case
inactive file is > 4Mb.
And don't decrease (with sc->priority increase) the size of required
inactive file cache when make a descision to scan file cache only.
2) the above leads to "has_inactive" is set only if
inactive file is > 4Mb.
3) if we did not reclaim anything while processing inactive file,
shrink active lists as well.
https://jira.sw.ru/browse/PSBM-92480
Signed-off-by: Andrey Ryabinin <[email protected]>
Acked-by: Konstantin Khorenko <[email protected]>
---
mm/vmscan.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
diff --git a/mm/vmscan.c b/mm/vmscan.c
index a122e4cfa1a4..d84ba1a5c4f8 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2208,9 +2208,11 @@ static void get_scan_count(struct lruvec *lruvec, struct
mem_cgroup *memcg,
/*
* There is enough inactive page cache, do not reclaim
* anything from the anonymous working set right now.
+ * We don't decrease the required level of inactive page cache
+ * with sc->priority decrease.
*/
if (!inactive_file_low &&
- lruvec_lru_size(lruvec, LRU_INACTIVE_FILE) >> sc->priority) {
+ lruvec_lru_size(lruvec, LRU_INACTIVE_FILE) >> (DEF_PRIORITY - 2)) {
scan_balance = SCAN_FILE;
goto out;
}
@@ -2262,7 +2264,7 @@ static void get_scan_count(struct lruvec *lruvec, struct
mem_cgroup *memcg,
fraction[1] = fp;
denominator = ap + fp + 1;
out:
- sc->has_inactive = !inactive_file_low ||
+ sc->has_inactive = (!inactive_file_low && (scan_balance == SCAN_FILE))
||
((scan_balance != SCAN_FILE) && !inactive_anon_low);
*lru_pages = 0;
for_each_evictable_lru(lru) {
@@ -2597,7 +2599,8 @@ static void shrink_zone(struct zone *zone, struct
scan_control *sc,
}
} while ((memcg = mem_cgroup_iter(root, memcg, &reclaim)));
- if (!sc->has_inactive && !sc->may_shrink_active) {
+ if ((!sc->has_inactive || !sc->nr_reclaimed)
+ && !sc->may_shrink_active) {
sc->may_shrink_active = 1;
retry = true;
continue;
_______________________________________________
Devel mailing list
[email protected]
https://lists.openvz.org/mailman/listinfo/devel
