On Sat, 2011-08-06 at 16:44 +0800, Wu Fengguang wrote: > > Add two fields to task_struct. > > 1) account dirtied pages in the individual tasks, for accuracy > 2) per-task balance_dirty_pages() call intervals, for flexibility > > The balance_dirty_pages() call interval (ie. nr_dirtied_pause) will > scale near-sqrt to the safety gap between dirty pages and threshold. > > 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(). Right, so why remove the per-cpu threshold? you can keep that as a bound on the number of out-standing dirty pages. Loosing that bound is actually a bad thing (TM), since you could have configured a tight dirty limit and lock up your machine this way. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
