Hi，Jason： As discussed last time，After setting conf_rbd_qos_bps_limit, the speed of discard is also limited， which can make operation such as mkfs.xfs very slow, though we can add -K option to solve this problem, but we can't make sure that other operation or application never call discard interface, so if the discard operation can be not limited by conf_rbd_qos_bps_limit option, and if so, is there any other risk? Thanks. Beset Regards， LiuGangbiao