This counts events where the receive-side PDV jitter buffer filled completely, forcing the device to discard incoming packets it had no room to buffer. Overrun on this pseudowire is the opposite failure mode from Underrun -- packets arriving faster or burstier than the buffer was sized for -- and a climbing count here suggests the buffer depth should be increased or the network path is delivering unexpectedly bursty traffic -- and this specific object covers a cumulative counter reset only by an explicit clear rather than on a fixed schedule -- reflecting everything since PM stats were last cleared. For example, since PM counters were last cleared, this pseudowire might show this counter at 25 -- a concrete count the admin can trend against neighboring bins to judge whether the condition it reflects is worsening.