Exactly as described, this is a running total of 802.3x PAUSE frames received on this benchmark port. PAUSE frames arriving here mean some downstream or far-end device is asking this port to slow its transmission, so during a generator test this counter incrementing would explain why the actual achieved transmit rate is lower than the test profile's configured bandwidth, without any frames actually being lost. For example, a throughput test showing zero frame loss but consistently under-target throughput, alongside a rising receive-pause count, points to flow control on the far end throttling the generator rather than any real network capacity limit.