Receive buffer size cannot be increased within Docker containers

[pirate]

Hi, I'm trying to use caddy (which uses quic-go v0.34.0) in Docker, and am encountering this error.

failed to sufficiently increase receive buffer size (was: 208 kiB, wanted: 2048 kiB, got: 416 kiB). See https://github.com/quic-go/quic-go/wiki/UDP-Receive-Buffer-Size for details.

However, the Docker Desktop VM on macOS (and maybe other OSs?) has neither the kern.ipc.maxsockbuf nor net.core.rmem_max sysctl settings settings available.

➜ ~/$ docker run --rm -it --privileged ubuntu /bin/bash

$ sysctl -w net.core.rmem_max=2097152
sysctl: cannot stat /proc/sys/net/core/rmem_max: No such file or directory

$ sysctl -w kern.ipc.maxsockbuf=3014656
sysctl: cannot stat /proc/sys/kern/ipc/maxsockbuf: No such file or directory

Is there any other way to increase the QUIC receive buffer, or get rid of this error message within docker? Thanks!

Versions:

• host OS: macOS 13.2.1 (arm64 M1)
• Docker Desktop: 23.0.5, build bc4487a
• quic-go version: 0.34.0 (from caddyserver/caddy/go.mod)

Related:

• https://discuss.ipfs.tech/t/docker-failed-to-sufficiently-increase-receive-buffer-size/12498/3
• investigate modifying the kernel's receive buffer size #2255

[marten-seemann]

Unfortunately I'm not familiar enough with Docker networking to solve this. We have a similar report in #3418, is this a duplicate?

[pirate]

Ah whoops, that is a duplicate. Not sure why I missed it when I searched earlier!

Unfortunately I don't think the EC2-specific resolution in #3418 works for Docker Desktop. Maybe someone else knows how to set the equivalent sysctl keys in macOS Docker Desktop's VM?
My attempt with --privileged didn't work :/

[marten-seemann]

@pirate Can you check if #3804 fixed the problem?

[pirate]

Is it ok if I wait for the next caddy release which includes this update? I don't know enough about go-quic to test it in isolation.

Feel free to close the issue if needed and I can reopen it if I see the error keep happening.

[marten-seemann]

Right, we introduced a bunch of breaking changes since the last release.

Is it ok if I wait for the next caddy release which includes this update?

Sure!

[mosajjal]

is it possible to suppress this warning or bring it back to the main application to deal with the message? in some scenarios, stderr logging might not be good enough.

[dinvlad]

@pirate have you or anyone else been able to address this in Docker Desktop or on a non-ECS host (and without --net host or --cap-add NET_ADMIN)?

[arashpayan]

is it possible to suppress this warning

If you'd like to suppress it, you can set the environment variable QUIC_GO_DISABLE_RECEIVE_BUFFER_WARNING to true

os.Setenv("QUIC_GO_DISABLE_RECEIVE_BUFFER_WARNING", "true")