...
Using IB send: 2.753 us
Using RDMA: 2.50495 us
RTT (RPC-style)
...
...
Using IB send: 4.969 us (explains write RPC latency seen in RAMCloud: 5 + 1 = 6 us)
Using RDMA: 4.866 us
We see that a one-way RDMA easily beats the round-trip IB send's currently used RAMCloud RPC.