Comment by tptacek

First, "just use" is doing a lot of work in that sentence, because DPDK is much harder to use than XDP. The authors of this blog were surprised they had to do their own checksumming, for instance.

Maybe more importantly: they're not building a middlebox. DPDK ultra-high performance comes in part from polling. It's always running. XDP is just an extension to the existing network driver.