Hi Ceph, I am wondering is there a mechanism to prioritize the rbd_aio_write/rbd_aio_read I/Os? Currently all RBD I/Os are issued in FIFO to rados layer, and there is NO QoS mechanism to control the priority of these I/Os. A QoS mechanism will be beneficial when performing certain management operations, such as flatten. When flatten a image, the outstanding I/Os do get throttled by “rbd_concurrent_management_ops”. However this won't guarantee normal I/Os are not affected, as outstanding normal I/Os are still competing with concurrent management ops. Anyone know how/where to implement this QoS mechanism? Thanks! Cheng -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html