The dirty_ratio was silently limited to >= 5%. This is not a user expected behavior. Let's rip it. It's not likely the user space will depend on the old behavior. So the risk of breaking user space is very low. CC: Jan Kara <jack@xxxxxxx> CC: Neil Brown <neilb@xxxxxxx> Signed-off-by: Wu Fengguang <fengguang.wu@xxxxxxxxx> --- mm/page-writeback.c | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) --- linux-next.orig/mm/page-writeback.c 2010-08-20 10:55:17.000000000 +0800 +++ linux-next/mm/page-writeback.c 2010-08-20 10:56:36.000000000 +0800 @@ -415,14 +415,8 @@ void global_dirty_limits(unsigned long * if (vm_dirty_bytes) dirty = DIV_ROUND_UP(vm_dirty_bytes, PAGE_SIZE); - else { - int dirty_ratio; - - dirty_ratio = vm_dirty_ratio; - if (dirty_ratio < 5) - dirty_ratio = 5; - dirty = (dirty_ratio * available_memory) / 100; - } + else + dirty = (vm_dirty_ratio * available_memory) / 100; if (dirty_background_bytes) background = DIV_ROUND_UP(dirty_background_bytes, PAGE_SIZE); -- 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>