dect
/
linux-2.6
Archived
13
0
Fork 0
Code Releases Activity

vmscan: low order lumpy reclaim also should use PAGEOUT_IO_SYNC 

Commit 33c120ed28 ("more aggressively use
lumpy reclaim") increased how aggressive lumpy reclaim was by isolating
both active and inactive pages for asynchronous lumpy reclaim on
costly-high-order pages and for cheap-high-order when memory pressure is
high.  However, if the system is under heavy pressure and there are dirty
pages, asynchronous IO may not be sufficient to reclaim a suitable page in
time.

This patch causes the caller to enter synchronous lumpy reclaim for
costly-high-order pages and for cheap-high-order pages when under memory
pressure.

Minchan.kim@gmail.com said:

Andy added synchronous lumpy reclaim with
c661b078fd.  At that time, lumpy reclaim is
not agressive.  His intension is just for high-order users.(above
PAGE_ALLOC_COSTLY_ORDER).

After some time, Rik added aggressive lumpy reclaim with
33c120ed28.  His intention was to do lumpy
reclaim when high-order users and trouble getting a small set of
contiguous pages.

So we also have to add synchronous pageout for small set of contiguous
pages.

Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Andy Whitcroft <apw@shadowen.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reviewed-by: Minchan Kim <Minchan.kim@gmail.com>
Reviewed-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
KOSAKI Motohiro 2009-06-16 15:31:40 -07:00 committed by Linus Torvalds
parent d2bf6be8ab
commit 78dc583d3a
1 changed files with 15 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
mm/vmscan.c
View File

@ -1061,6 +1061,19 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
unsigned long nr_scanned = 0;
unsigned long nr_reclaimed = 0;
struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
int lumpy_reclaim = 0;
/*
* If we need a large contiguous chunk of memory, or have
* trouble getting a small set of contiguous pages, we
* will reclaim both active and inactive pages.
*
* We use the same threshold as pageout congestion_wait below.
*/
if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
lumpy_reclaim = 1;
else if (sc->order && priority < DEF_PRIORITY - 2)
lumpy_reclaim = 1;
pagevec_init(&pvec, 1);
@ -1073,19 +1086,7 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
unsigned long nr_freed;
unsigned long nr_active;
unsigned int count[NR_LRU_LISTS] = { 0, };
int mode = ISOLATE_INACTIVE;
/*
* If we need a large contiguous chunk of memory, or have
* trouble getting a small set of contiguous pages, we
* will reclaim both active and inactive pages.
*
* We use the same threshold as pageout congestion_wait below.
*/
if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
mode = ISOLATE_BOTH;
else if (sc->order && priority < DEF_PRIORITY - 2)
mode = ISOLATE_BOTH;
int mode = lumpy_reclaim ? ISOLATE_BOTH : ISOLATE_INACTIVE;
nr_taken = sc->isolate_pages(sc->swap_cluster_max,
&page_list, &nr_scan, sc->order, mode,
@ -1122,7 +1123,7 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
* but that should be acceptable to the caller
*/
if (nr_freed < nr_taken && !current_is_kswapd() &&
sc->order > PAGE_ALLOC_COSTLY_ORDER) {
lumpy_reclaim) {
congestion_wait(WRITE, HZ/10);
/*