Debating the value of XDP

Posted Dec 8, 2016 22:40 UTC (Thu) by raven667 (subscriber, #5198)
Parent article: Debating the value of XDP

If you are going down the eBPF path, why not go all the way and replace all of the hand-optimized C network stack with a eBPF (or similar) VM running in kernel or in userspace that is machine optimized? You can expose some efficient datastructures to it which may be hand-optimized for state tracking when needed. This all starts to look like GPU shader programs at some point 8-)

Debating the value of XDP

Posted Dec 9, 2016 18:19 UTC (Fri) by ksandstr (guest, #60862) [Link]

>This all starts to look like GPU shader programs at some point 8-)

It's looking like mid-to-late nineties Direct3D right now. Predicting from that, it seems unlikely that current XDP programs will ever be translated into bytecoded hardware-supported mysteriously zomgfast[0] acceleration primitives on networking hardware. As such, they're strictly inferior to models like "a compiled C program executing in kernel mode" or, in the absence of a magical in-kernel compiler infrastructure, any fixed-function acceleration pipeline at all.

[0] and not just "0.7 GHz ARM SOC w/ OpenCL, on a PCIe board": just another channel processor with a proprietary interface