The problem is even simpler than that – the H1280 is a PCIe 3 HBA. Your Mac only offers PCIe 2 slots. You will never see the performance you expect out of that HBA on a Mac system. While it may “Work” it’s severely hampered by the x4 PCIe 2 slot you have available on that system.
So far as your BRU Server configuration, you’re running about as good as you’ll get until you can move to a platform with true PCIe 3 support. The only change you may wish to try is if the Server and Client are the same system, be sure that you are using “localhost” or 127.0.0.1 for the network setting for both ends to keep the traffic internal to the system’s network stack.
Yes, it is a PCIe 3 card, but even with the slot it is in (which, I’ll admit, is a PCIe 1.1 slot at x4), it should still be able to push 1GB/s of data according to PCIe spec, right? I’m only getting 150MB/s to tape according to BRU. Unless the H1280 is doing something weird and falling back even slower, it seems odd that I wouldn’t be getting faster transfers from the card.
And my server is accessing itself using localhost.
Apologies, Doug, no, nothing has changed. Even moving to the 5,1 Mac Pro and putting the H1280 in slot 2, which is an x16 slot, I am still only getting 2.5GT/s at x8…which should still be fast enough to push enough data to the tape drive.