Huh, that's interesting. That seems weird to me, but I suppose it could technically make things faster assuming things like checksum failures are rare. I suppos

Huh, that's interesting. That seems weird to me, but I suppose it could technically make things faster assuming things like checksum failures are rare. I suppose the reason might be that they can mark the socket while still in the interrupt handler, but I haven't read those parts of the kernel close enough to know if they actually do such a thing. But either way, I would agree, if you don't want blocking then just use O_NONBLOCK, it's the intended way and it's the best way.