Files
firezone/rust
Thomas Eizinger 2545c41366 refactor(connlib): move client phoenix-channel to separate task (#10210)
Currently, `connlib`'s event-loop for clients uses manual polling to
advance the state of the tunnel and the phoenix-channel. Manual polling
is powerful but also easy to get wrong, resulting in task-wakeup bugs.

Additionally, if the tunnel is very busy with processing packets, the
phoenix-channel may not get enough CPU time, resulting in a loss of the
WebSocket connection.

To fix this, we move the phoenix-channel to a separate task and use
channels to connect it with `connlib`'s main event-loop. This one is now
primarily focused on advancing the tunnel state, effectively offloading
the problem of fair scheduling to the tokio runtime.

Related: #10003
2025-08-18 07:20:57 +00:00
..
2023-05-10 07:58:32 -07:00

Rust development guide

Firezone uses Rust for all data plane components. This directory contains the Linux and Windows clients, and low-level networking implementations related to STUN/TURN.

We target the last stable release of Rust using rust-toolchain.toml. If you are using rustup, that is automatically handled for you. Otherwise, ensure you have the latest stable version of Rust installed.

Reading Client logs

The Client logs are written as JSONL for machine-readability.

To make them more human-friendly, pipe them through jq like this:

cd path/to/logs  # e.g. `$HOME/.cache/dev.firezone.client/data/logs` on Linux
cat *.log | jq -r '"\(.time) \(.severity) \(.message)"'

Resulting in, e.g.

2024-04-01T18:25:47.237661392Z INFO started log
2024-04-01T18:25:47.238193266Z INFO GIT_VERSION = 1.0.0-pre.11-35-gcc0d43531
2024-04-01T18:25:48.295243016Z INFO No token / actor_name on disk, starting in signed-out state
2024-04-01T18:25:48.295360641Z INFO null

Benchmarking on Linux

The recommended way for benchmarking any of the Rust components is Linux' perf utility. For example, to attach to a running application, do:

  1. Ensure the binary you are profiling is compiled with the release profile.
  2. sudo perf record -g --freq 10000 --pid $(pgrep <your-binary>).
  3. Run the speed test or whatever load-inducing task you want to measure.
  4. sudo perf script > profile.perf
  5. Open profiler.firefox.com and load profile.perf

Instead of attaching to a process with --pid, you can also specify the path to executable directly. That is useful if you want to capture perf data for a test or a micro-benchmark.