enricobuehler
9f92dc505b
The client asks the kernel for a 32 MB SO_RCVBUF, but the kernel silently clamps it to net.core.rmem_max — whose default is far too small. A too-small recv buffer is the dominant client-side wall above ~1 Gbps. Measured live (Fedora host -> two clients, real 2.5G LAN, GSO off): a client capped at 4 MB rmem_max dropped 31.6% of a 2 Gbps stream at the receiver, while a 32 MB client delivered the same 2 Gbps at 0.0% loss. The host already shipped this tuning; the client packages didn't (the RPM's %post even referenced the host-only file), so a client-only install streamed lossy at high bitrate. Add scripts/99-punktfunk-client-net.conf (rmem/wmem = 32 MB, distinct filename so host+client can coexist) and ship+apply it from both the .deb (build-client-deb.sh) and the RPM client subpackage (install, %files client, %post client). For reference the full ladder (punktfunk speed-test): 0% loss to 1.5 Gbps on a 4 MB client; 31.6% at 2 Gbps on 4 MB vs 0% at 2 Gbps on 32 MB. iperf3 put the raw link at ~2.35 Gbps TCP / ~2.4 Gbps UDP, so the stack now tracks the wire given a big enough recv buffer. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
punktfunk-host — Debian/Ubuntu package (apt)
punktfunk-host is published as a .deb to Gitea's Debian package registry in the public
unom org, so the Ubuntu hosts update with plain apt. CI (.gitea/workflows/deb.yml) builds
and publishes on every push to main (a rolling 0.0.1~ciN.<sha> build) and on v* tags
(a clean X.Y.Z).
Package layout mirrors the Fedora RPM (../rpm/punktfunk.spec): the host binary, the /dev/uinput
udev rule, the systemd user unit, headless session helpers, the example config, and the OpenAPI
doc. Runtime Depends are computed by dpkg-shlibdeps from the binary itself (built in the Ubuntu
26.04 rust-ci image, so the lib soname package names match the target). The NVIDIA driver
(libnvidia-encode / libEGL_nvidia / libcuda) is not a dependency — it's installed out of
band, like on the RPM side.
Install on a host (one-time)
The registry is public, so no apt auth is needed — just trust the repo's signing key:
sudo install -d -m 0755 /etc/apt/keyrings
curl -fsSL https://git.unom.io/api/packages/unom/debian/repository.key \
| sudo tee /etc/apt/keyrings/punktfunk.asc >/dev/null
echo "deb [signed-by=/etc/apt/keyrings/punktfunk.asc] https://git.unom.io/api/packages/unom/debian stable main" \
| sudo tee /etc/apt/sources.list.d/punktfunk.list
sudo apt update
sudo apt install punktfunk-host
Then, as the desktop user:
sudo usermod -aG input "$USER" # virtual gamepads (re-login to take effect)
mkdir -p ~/.config/punktfunk
cp /usr/share/punktfunk-host/host.env.example ~/.config/punktfunk/host.env # then edit
systemctl --user enable --now punktfunk-host
Updates
sudo apt update && sudo apt upgrade # picks up the newest published build
systemctl --user restart punktfunk-host # if the unit was already running
Build a .deb locally
VERSION=0.0.1 bash packaging/debian/build-deb.sh # -> dist/punktfunk-host_0.0.1_amd64.deb
Needs dpkg-dev (dpkg-shlibdeps, dpkg-deb). It builds the release binary first if missing.
Build it in the rust-ci image (or on an Ubuntu 26.04 box) so the resolved Depends match the
hosts; building on a GPU box is fine — the NVIDIA driver lib is filtered out either way.