[p2pBandwidthLatencyTest] what is the CPU latency ?

In the last two test results, we can see the matrix indicted GPU latency and CPU latency.

What’s the CPU latency here? In my test, it is a ‘PIX’ connection topology. ( got it from ‘nvidia-smi topo -m’ )

The two testing GPU card should under the same CPU, does it mean the latency caused by CPU since packet will route via CPU even in PIX topology?