BPF at Facebook and beyond
> Facebook, he began, has an upstream-first philosophy, taken to an extreme; the company tries not to carry any out-of-tree patches at all. All work done at Facebook is meant to go upstream as soon as it practically can. The company also runs recent kernels, upgrading whenever possible.I was chatting to a Facebook engineer on their use of BPF this summer and heard the same thing, which was surprising to me. There seem to be a number of companies that take advantage of Linux being licensed under GPL and keep their own forks/patches of the kernel that they use internally (anecdotally, I’ve heard Google does this), and the they stay on some old version, which apparently Facebook doesn’t do.