This is just an RFC to reduce some of the more obvious stack usage in page reclaim. It's a bit rushed and I haven't tested this yet but am sending it out as there may be others working on similar material and would rather avoid overlap. I built on some of Kosaki Motohiro's work. On X86 bit, stack usage figures (generated using a modified bloat-o-meter that uses checkstack.pl as its input) change in the following ways after the series of patches. add/remove: 2/0 grow/shrink: 0/4 up/down: 804/-1688 (-884) function old new delta putback_lru_pages - 676 +676 update_isolated_counts - 128 +128 do_try_to_free_pages 172 128 -44 kswapd 1324 1168 -156 shrink_page_list 1616 1224 -392 shrink_zone 2320 1224 -1096 There are some growths there but critically they are no longer in the path that would call writepages. In the main path, there is about 1K of stack lopped off giving a small amount of breathing room. KOSAKI Motohiro (3): vmscan: kill prev_priority completely vmscan: move priority variable into scan_control vmscan: simplify shrink_inactive_list() Mel Gorman (7): vmscan: Remove useless loop at end of do_try_to_free_pages vmscan: Remove unnecessary temporary vars in do_try_to_free_pages vmscan: Split shrink_zone to reduce stack usage vmscan: Remove unnecessary temporary variables in shrink_zone() vmscan: Setup pagevec as late as possible in shrink_inactive_list() vmscan: Setup pagevec as late as possible in shrink_page_list() vmscan: Update isolated page counters outside of main path in shrink_inactive_list() include/linux/mmzone.h | 15 -- mm/page_alloc.c | 2 - mm/vmscan.c | 447 +++++++++++++++++++++++------------------------- mm/vmstat.c | 2 - 4 files changed, 210 insertions(+), 256 deletions(-) -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>