since ros 7.15 QoS Hardware Offloading (QoS-HW) is avaliable
documentation
https://help.mikrotik.com/docs/pages/viewpage.action?pageId=189497483
official topic about it
http://forum.mikrotik.com/t/qos-hardware-offloading-qos-hw/166573/1
enabling QoS Hardware Offloading you can monitor buffer status and also tune and monitor some settings related to buffers in a global way and also specific to each interface, i think this can help you
off course this features are available using RouterOS not SWOS