Tweaking FreeNAS and ESXi for 10Gbps

[Dudde]

If i run

Code:

iperf -s -B 10.10.117.220

with FreeNAS as the server i get these results

Code:

------------------------------------------------------------
Client connecting to 10.10.117.220, TCP port 5001
TCP window size: 35.0 KByte (default)
------------------------------------------------------------
[  3] local 10.10.117.210 port 28528 connected with 10.10.117.220 port 5001
[ ID] Interval  Transfer  Bandwidth
[  3]  0.0-30.0 sec  38.5 GBytes  11.0 Gbits/sec

But if i let ESXi act as server with the same commands i get these results

Code:

------------------------------------------------------------
Server listening on TCP port 5001
Binding to local address 10.10.117.210
TCP window size: 64.0 KByte (default)
------------------------------------------------------------
[  4] local 10.10.117.210 port 5001 connected with 10.10.117.220 port 34654
[ ID] Interval  Transfer  Bandwidth
[  4]  0.0-30.0 sec  18.8 GBytes  5.37 Gbits/sec

What could be the problem here?

 

[dlavigne]

Did you find the answer to your question?

 

[bigphil]

We need more info to be able to help you out here.
FreeNAS version?
Any tunables enabled?
ESXi version?
NIC model (both sides)?
Any NIC options set?
Physical connectivity (switch, optics, DAC)?

I just performed the same two test from FreeNAS 9.10.2-U5 <> ESXi 6.5 (both using Intel X710-DA4 10Gb NIC's) and got 9.24 Gbits/sec (FreeNAS as server) and 9.15 Gbits/sec (ESXi as server).
server: iperf -s -B local_IP
client: iperf -m -i 1 -t 30 -c server_IP -f M