Chelsio 10G & 40G cards max out around 3Gbps
Cards seem to have a buffer fill and start sending flow control pause frames. Working directly with Chelsio for resolution. Created ticket to track the issue.
At first they suggested adding the following to /etc/system, but it had no noticeable impact on performance
Updated by Jason Matthews about 2 months ago
Got this back from Chelsio...
Our Engineering is able to find below observations. Engineering is still investigating the issue. Will post progress tomorrow. JFI….we didn’t use your setup.
1. This could be an Rx issue seen only with AMD CPU.
2. With Linux peer, seeing line rate
when smartOS is the sender.
3. same low Rx performance is also seen on Intel, QLogic & Emulex 10G
4. Rx issue is not seen when OpenIndiana (with CPU affinity configured) is
installed on the same AMD setup.
5. Configuring CPU affinity using dladm on smartOS is not giving expected
results. Looking into this…
Command to configure CPU affinity.
#dladm set-linkprop -p cpus=0-11 cxgbe0