On Tue, Jul 09, 2013 at 05:43:10PM +0400, Konstantin Khlebnikov wrote: > My concept it cgroup which would control io operation on vfs layer > for all filesystems. It will account and manage IO operations. I've > found really lightweight technique for accounting and throttling > which don't introduce new locks or priority inversions (which is > major problem in all existing throttlers, including cpu cgroup rate > limiter) So, I've tried to keep code smaller, cleaner and saner as > possible while you guys are trying to push me into the block layer > =) You're trying to implement QoS in the place where you don't have control of the queue itself. You aren't even managing the right type of resource for disks which is time slice rather than iops or bandwidth and by the time you implemented proper hierarchy support and proportional control, yours isn't gonna be that simple either. The root problem is bdi failing to propagate pressure from the actual queue upwards. Fix that. -- tejun -- 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>