The first half of the 6.6 merge window [LWN.net]

The first half of the 6.6 merge window

Posted Aug 31, 2023 16:45 UTC (Thu) by Cyberax (✭ supporter ✭, #52523)
Parent article: The first half of the 6.6 merge window

> A new BPF hook (update_socket_protocol) allows a BPF program to change the requested protocol for a new socket. Its primary purpose seems to be to transparently cause programs requesting TCP connections to use multipath TCP instead. MPTCP has also gained some initial support for BPF programs that route packets to different subflows.

It seems like this functionality should be represented via a normal prctl() option, rather than via ad-hoc BPF hooks.

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The first half of the 6.6 merge window

Posted Sep 20, 2023 11:40 UTC (Wed) by ghane (guest, #1805) [Link] (4 responses)

Is MP-TCP in actual use on the public internet? I am not aware of any deployments except test beds.

Information welcome.

--
Sanjeev

The first half of the 6.6 merge window

Posted Sep 20, 2023 20:48 UTC (Wed) by Cyberax (✭ supporter ✭, #52523) [Link] (2 responses)

Apple uses it for Siri: https://www.tessares.net/apples-mptcp-story-so-far/

The first half of the 6.6 merge window

Posted Sep 20, 2023 23:36 UTC (Wed) by Fowl (subscriber, #65667) [Link] (1 responses)

I’d be surprised if they hadn’t moved to or at least planned to add QUIC/HTTP3.

Wonder how long until we see that in the kernel. SMB3 has a QUIC transport now, for example. Perhaps even the first(?) io_uring exclusive user space API - at least on the server - the browser people like to keep control. /musings

The first half of the 6.6 merge window

Posted Sep 23, 2023 21:06 UTC (Sat) by Cyberax (✭ supporter ✭, #52523) [Link]

It still uses it.

Siri has to work with all kinds of crappy hotel networks, so QUIC is not an option. It relies on UDP which is frequently blocked. MP-TCP is basically just TCP, so it works everywhere.

The first half of the 6.6 merge window

Posted Sep 23, 2023 8:28 UTC (Sat) by mupuf (subscriber, #86890) [Link]

We used it to broadcast cycling competitions over the 4G network in Finland. Each motorcycle-mounted camera had four 4G modems with SIM cards from different providers.

Worked wonderfully well! It was good-enough for live national TV too :)