This read-only PerfCounter64 counts Frames WRED Dropped by this traffic port's QoS shaper during the interval, meaning frames proactively discarded by Weighted Random Early Detection before the port's queue became completely full. A nonzero count shows an administrator that congestion management is preemptively shedding some load on this specific port to avoid a harder tail-drop event. For example, seeing cmTrafficPortQosShaperStatsFREDD rise modestly while cmTrafficPortQosShaperStatsFTD stays at zero on the same port suggests WRED is successfully preventing full queue overflow there.