This read-only counter reports the total number of cells dropped across all channels on the port because their ingress queues were full, summing the per-channel ingress-queue-full discard statistics into one port-level total. An administrator checks this counter to quickly assess whether ingress congestion is a port-wide problem before drilling into individual channel statistics. A rapidly climbing total while individual channel counters stay modest suggests the discards are spread across many channels rather than concentrated on one.