This read-only counter tallies how many cells received in the ingress direction already had their EFCI (Explicit Forward Congestion Indication) bit set upon arrival, meaning some upstream network element had already flagged congestion before the cell reached this switch. Admins use this to detect congestion occurring further upstream in the network path feeding this channel, separate from any congestion this local switch itself might introduce. For example, a rising chanIngrEfciSetRcvCells count would tell the admin that congestion is originating somewhere upstream of this card, not necessarily at this local queue.