Onload Latency with netperf

You can measure Onload latency with standard tools. This test identifies how to use netperf.

Run the netserver application on system-1:

[sys-1]# pkill -f netserver
[sys-1]# onload --profile=<profile> taskset -c 1 netserver

and the netperf application on system-2:

[sys-2]# onload --profile=<profile> taskset -c 1 \
    netperf -t <test> -H <sys-1_ip> -l 10 -- -r <payload>

where:

• <profile> is latency-best for 10 Gb (which uses cut-through CTPIO), or latency for 25 Gb (which uses store and forward (no-poison) CTPIO)
• <test> is UDP_RR or TCP_RR, as appropriate
• <payload> is the payload size, in bytes
• <sys-1_ip> is the IP address of sys-1.

The output identifies the transaction rate per second, from which:

mean ½ RTT = (1 / transaction rate) / 2