Test-RDMA throughput is limited by storage system, not network

[4fd81048-Brian]

Test-RDMA diskspd throughput is limited by the storage subsystem and doesn't fully test the network link reliability.

I have submitted Pull #472 that changes the parameters to DiskSpd to use caching on the remote end (-Sr) and uses -ft to set FILE_ATTRIBUTE_TEMPORARY access hint that results in the IO to not be flushed on the backing media.

The result is that any RDMA network link is fully saturated during the test.

References:
https://unhandled.wordpress.com/2016/07/20/madness-testing-smb-direct-network-throughput-with-diskspd/