iPerf on 10Gbps

[batiati]

Hi, folks

I'm benchmarking my environment, but I'm a bit confused about the propper whay to use the iPerf3 tool on a 10Gbps connection:

When I run iPerf like ".\iperf3.exe -c 10.10.1.1", my results are about 4Gbps.
So, I had to specify ".\iperf3.exe -c 10.10.1.1 -P 4" for four parallel workers in order to achieve 10Gbps on this link.
Is that correct? Was it expected to have 10Gbps on a single worker? There is any recommended parameters to benchmark 10Gbps on iPerf?

My hardware is a Dell R610 with 2 x Broadcom NetExtreme II BCM57711 dual 10Gbps DAC apater.
I was testing the SYNC link, directly attached between two machines, but no notticiable difference testing same thing trough the SAN link connected on the 10Gbps switch.

Thanks a lot

[Boris (staff)]

Unfortunately, I cannot confirm I have seen 10Gbps Broadcom based NICs that would hit at least 6Gbps.
You can try the following command and see whether that changes anything:

Code: Select all

.\iperf3.exe -c 10.10.1.1 -P 4 -w 16M

Hope that helps.

[batiati]

Thank you for replying

Unfortunately, I cannot confirm I have seen 10Gbps Broadcom based NICs that would hit at least 6Gbps.
You can try the following command and see whether that changes anything:

Code: Select all

.\iperf3.exe -c 10.10.1.1 -P 4 -w 16M

Hope that helps.

Nope, nothing changes with -w 16M.

If I put -P 4 argument I can reach 10Gbps;


Without -P I got almost 5Gbps.



So, since I reached 10Gbps, should I consider my link OK or should I have 10Gbps without -P argument?

[Boris (staff)]

Your link is OK as long as you can reach 10Gbps.