This reports the number of packet buffers currently in use on this node, applicable to all platforms except the VG100. This is the usage-side counterpart to the packet buffer availability figure, and an admin watches the two together the same way as the data-buffer pair, to distinguish steady-state packet-processing load from an abnormal upward creep suggesting a leak or sustained congestion. For example, packet buffer usage plateauing at a consistent 60% during business hours every day would establish a healthy baseline against which future anomalies can be judged.