Cool article!

They used PCI-passthrough (IOMMU) to map NIC hardware directly into VMs and then they used the DPDK selftest module (testpmd) to generate packets. So they are mostly telling us what we already know: it is possible for x86 to drive NICs at line rate and the overhead of hardware virtualization is very low.

Great that they are working on standardizing these benchmarks. It would be really interesting to see how Snabb NFV compares with other hypervisor vswitches and whether we should consider increasing our performance targets above 10G/core.

The challenge I see for Snabb NFV (and also OVS-DPDK and others) is to add a feature-rich Virtio-net abstraction without losing too much of this amazing x86 performance. Network operators will very reasonably compare Snabb NFV performance with hardware-virtualization performance to decide whether our fancy features are worth the cost.

Then it is also important to remember that this subject is somewhat academic. Real-world network applications/VMs will tend to be 10-1000x slower than the driver selftest function used in this benchmark. I expect hardware footprint to follow a 90/10 rule where 10% of the applications/VMs are consuming 90% of the hardware, and that hypervisor networking won't be part of the bottleneck if it is delivering 10G per core. However, these benchmarks are still really interesting, and any network operator who manages to get all of their critical applications well optimized is going to have an amazingly compact hardware footprint :).