On Thu, Apr 15, 2010 at 06:21:33PM +0100, Mel Gorman wrote: > 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. > So the first pass seems to have been reasonably well received. Kosaki, Rik and Johannes, how you do typically test reclaim-related patches for regressions? My initial sniff-tests look ok with the page leak sorted out but I typically am not searching for vmscan regressions other than lumpy reclaim. > On X86 bit, stack usage figures (generated using a modified bloat-o-meter This should have been X86-64. The stack shrinkage is less on X86 obviously because of the difference size of pointers and the like. > 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(-) > -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
