On Wed, Dec 8, 2010 at 5:04 PM, KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote: >> invalidate_mapping_pages is very big hint to reclaimer. >> It means user doesn't want to use the page any more. >> So in order to prevent working set page eviction, this patch >> move the page into tail of inactive list by PG_reclaim. >> >> Please, remember that pages in inactive list are working set >> as well as active list. If we don't move pages into inactive list's >> tail, pages near by tail of inactive list can be evicted although >> we have a big clue about useless pages. It's totally bad. >> >> Now PG_readahead/PG_reclaim is shared. >> fe3cba17 added ClearPageReclaim into clear_page_dirty_for_io for >> preventing fast reclaiming readahead marker page. >> >> In this series, PG_reclaim is used by invalidated page, too. >> If VM find the page is invalidated and it's dirty, it sets PG_reclaim >> to reclaim asap. Then, when the dirty page will be writeback, >> clear_page_dirty_for_io will clear PG_reclaim unconditionally. >> It disturbs this serie's goal. >> >> I think it's okay to clear PG_readahead when the page is dirty, not >> writeback time. So this patch moves ClearPageReadahead. >> >> Signed-off-by: Minchan Kim <minchan.kim@xxxxxxxxx> >> Acked-by: Rik van Riel <riel@xxxxxxxxxx> >> Acked-by: Mel Gorman <mel@xxxxxxxxx> >> Cc: Wu Fengguang <fengguang.wu@xxxxxxxxx> >> Cc: KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> >> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> >> Cc: Nick Piggin <npiggin@xxxxxxxxx> > > Until anyone should data, I will not ack this. This patch increase > VM state, but benefit is doubious. Make sense to me. If Ben is busy, I will measure it and send the result. Thanks! -- Kind regards, Minchan Kim -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>