Changelog: *v1 -> v2: also update the stale comments about default transparent hugepage support pointed by Wanpeng Li. Since commit 13ece886d9(thp: transparent hugepage config choice), transparent hugepage support is disabled by default, and TRANSPARENT_HUGEPAGE_ALWAYS is configured when TRANSPARENT_HUGEPAGE=y. And since commit d39d33c332(thp: enable direct defrag), defrag is enable for all transparent hugepage page faults by default, not only in MADV_HUGEPAGE regions. Signed-off-by: Jianguo Wu <wujianguo@xxxxxxxxxx> --- mm/huge_memory.c | 11 ++++++----- 1 files changed, 6 insertions(+), 5 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index a92012a..90ce6de 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -27,11 +27,12 @@ #include "internal.h" /* - * By default transparent hugepage support is enabled for all mappings - * and khugepaged scans all mappings. Defrag is only invoked by - * khugepaged hugepage allocations and by page faults inside - * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived - * allocations. + * By default transparent hugepage support is disabled in order that avoid + * to risk increase the memory footprint of applications without a guaranteed + * benefit. When transparent hugepage support is enabled, is for all mappings, + * and khugepaged scans all mappings. + * Defrag is invoked by khugepaged hugepage allocations and by page faults + * for all hugepage allocations. */ unsigned long transparent_hugepage_flags __read_mostly = #ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS -- 1.7.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>