This statistic shows IP payload bytes/second, excluding the Ethernet/IB and IP headers.
Rarely. Network throughput monitoring can be achieved using the standard Analytics statistic Network: Device bytes, which is enabled and achived by default. Examining by-client throughput can usually be achieved through the Protocol statistic (for example, Protocol: iSCSI bytes, which allows other useful breakdowns based on the protocol). This statistic is most useful if the previous two were not appropriate for some reason.