2 ms·
Is it not considered a protocol violation to deliver out of order segments to the upper layer? That seems the same to me as abusing it to not require retransmit
by kortilla 4y ago
Is it not considered a protocol violation to deliver out of order segments to the upper layer? That seems the same to me as abusing it to not require retransmits either.
Remember, middle boxes can fully adhere to the TCP standards and terminate your TCP connection and enforce ordering. If you notice that, you’re not really following the protocol, you’re just using its header format.
- hinkley 4y agoYes, but. My read of the room is that he's conflating wire level and kernel level problems with userspace problems, which is a no-no because if Berkeley userspace has latency problems, we can deal with that separately from undoing 40 years of tribal knowledge in the process. In the video he says that he was seeing 3x of theoretical latency to userspace that he fixed with Homa, but similar efforts to fix Berkeley Sockets saw 'almost a 2x' improvement which he deemed insufficient. A question I'd like to see answered over the next couple years is what IO APIs will be the most efficient in a world where io_uring is everywhere.