Hi Rage,
Thanks very much for your reply. Apologies for my late response, it's been a busy couple of weeks.
1. The driver is 5.22.12433.0 and firmware 2.36.5000. This was the latest as of a couple of weeks ago.
2. nd_write_bw results:
#qp #bytes #iterations MR [Mmps] Gb/s CPU Util.
0 1048576 22712 0.004 31.75 100.00
I'm not sure why the CPU is displayed at 100% as it is actually using about 4%.
3. I have looked at the performance tuning PDF before and run the balanced tuning option in the driver configuration.
4. This is the results when they are plugged into each other back to back (even worse!):
c:\temp\NTttcp-v5.31\x64>ntttcp.exe -s -m 8,*,192.168.100.11 -l 128k -a 2 -t 30
Copyright Version 5.31
Network activity progressing...
Thread Time(s) Throughput(KB/s) Avg B / Compl
====== ======= ================ =============
0 30.114 773.594 131072.000
1 29.551 60.641 131072.000
2 30.021 2890.776 131072.000
3 30.911 62.114 131072.000
4 30.036 762.818 131072.000
5 29.895 706.473 131072.000
6 31.536 60.883 131072.000
7 29.926 774.176 131072.000
##### Totals: #####
Bytes(MEG) realtime(s) Avg Frame Size Throughput(MB/s)
================ =========== ============== ================
178.625000 30.000 3903.587 5.954
Throughput(Buffers/s) Cycles/Byte Buffers
===================== =========== =============
47.633 327.094 1429.000
DPCs(count/s) Pkts(num/DPC) Intr(count/s) Pkts(num/intr)
============= ============= =============== ==============
583.767 0.419 4805.100 0.051
Packets Sent Packets Received Retransmits Errors Avg. CPU %
============ ================ =========== ====== ==========
47982 7338 3356 6 4.445
As the switch has now been ruled out, I will also contact HP to see if they can offer some support.
Thanks again for help with this.
Zak