The patch titled vmscan: avoid setting zone congested if no page dirty has been added to the -mm tree. Its filename is vmscan-avoid-set-zone-congested-if-no-page-dirty.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: vmscan: avoid setting zone congested if no page dirty From: Shaohua Li <shaohua.li@xxxxxxxxx> nr_dirty and nr_congested are increased only when the page is dirty. So if all pages are clean, both them will be zero. In this case, we should not mark the zone congested. Signed-off-by: Shaohua Li <shaohua.li@xxxxxxxxx> Reviewed-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Minchan Kim <minchan.kim@xxxxxxxxx> Acked-by: Mel Gorman <mel@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/vmscan.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff -puN mm/vmscan.c~vmscan-avoid-set-zone-congested-if-no-page-dirty mm/vmscan.c --- a/mm/vmscan.c~vmscan-avoid-set-zone-congested-if-no-page-dirty +++ a/mm/vmscan.c @@ -913,7 +913,7 @@ keep_lumpy: * back off and wait for congestion to clear because further reclaim * will encounter the same problem */ - if (nr_dirty == nr_congested) + if (nr_dirty == nr_congested && nr_dirty != 0) zone_set_flag(zone, ZONE_CONGESTED); free_page_list(&free_pages); _ Patches currently in -mm which might be from shaohua.li@xxxxxxxxx are linux-next.patch mm-page-allocator-adjust-the-per-cpu-counter-threshold-when-memory-is-low.patch vmscan-avoid-set-zone-congested-if-no-page-dirty.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html