Netdev 0x16 - Keynote: It's Time to Replace TCP in the Datacenter

If you'd like to watch Ousterhoust explain Homa and his vision of replacing TCP: link to this video Spoiler: Ousterhout is right, and the data shows he is right. Maybe not everyone knows it yet, or it's the kind of "right" that not everyone will ever get to (and we'll settle for "good enough" for much longer), but he is almost certainly right. Not to disparage the poster of this article of course -- I always love a good hot take or contrarian piece.

…the datacenter, where in theory modern hardware is capable of delivering RPC messages with microsecond scale latency but in practice no RPC systems built on TCP come anywhere close to that. The Netdev talk I've linked below is really good and John makes a really thorough presentation of his ideas and what he's actually trying to optimize for. 1: link to this video…

If you want to watch Outsterhout in talk form: Netdev 0x16 - Keynote: It's time to replace TCP in the datacenter: link to this video Netdev is an amazing conference btw, it is insane that we get access to the trailblazing being shown off at conferences for free on places like YT.

…IO operations usually don't block (you merely memcpy, and the kernel flushes asynchronously in the background). That can only take you so far, however, and it's apparent today that hardware can go much further and that the gap is widening. It's a valid point, though, to question whether that additional performance is even needed. John Ousterhout ( link to this video ) is currently working on a new network protocol to alleviate some of the problems TCP creates in software wrt performance, and he also questions whether there is even a need for very fast networking for real-world applications. IMO, the mere existence of stuff like DPDK is proof enough. Many folks use it and would rather use the kernel if…