From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Subject: Re: [PATCH 4/5] writeback: per task dirty rate limit Date: Mon, 08 Aug 2011 15:47:14 +0200 Message-ID: <1312811234.10488.34.camel@twins> References: <20110806084447.388624428@intel.com> <20110806094527.002914580@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Cc: linux-fsdevel@vger.kernel.org, Andrew Morton , Jan Kara , Christoph Hellwig , Dave Chinner , Greg Thelen , Minchan Kim , Vivek Goyal , Andrea Righi , linux-mm , LKML To: Wu Fengguang Return-path: In-Reply-To: <20110806094527.002914580@intel.com> Sender: owner-linux-mm@kvack.org List-Id: linux-fsdevel.vger.kernel.org On Sat, 2011-08-06 at 16:44 +0800, Wu Fengguang wrote: > Add two fields to task_struct. >=20 > 1) account dirtied pages in the individual tasks, for accuracy > 2) per-task balance_dirty_pages() call intervals, for flexibility >=20 > The balance_dirty_pages() call interval (ie. nr_dirtied_pause) will > scale near-sqrt to the safety gap between dirty pages and threshold. >=20 > XXX: The main problem of per-task nr_dirtied is, if 10k tasks start > dirtying pages at exactly the same time, each task will be assigned a > large initial nr_dirtied_pause, so that the dirty threshold will be > exceeded long before each task reached its nr_dirtied_pause and hence > call balance_dirty_pages(). >=20 > Signed-off-by: Wu Fengguang > --- > include/linux/sched.h | 7 ++ > mm/memory_hotplug.c | 3 - > mm/page-writeback.c | 106 +++++++++------------------------------- > 3 files changed, 32 insertions(+), 84 deletions(-)=20 No fork() hooks? This way tasks inherit their parent's dirty count on clone(). -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org