f44fdb7fa3
For all STUN and TURN messages that are being sent from `connlib`, we implement a retransmit strategy with an exponential backoff if we don't hear from the relay within a given amount of time. For this, we are currently using the `backoff` crate. For our purposes, this crate is a bit unergonomic. In particular, it has a mutable `next_backoff` function as well as internal dependency on a "clock". As a consequence, we need to a) always make sure the clock of an `ExponentialBackoff` is pointing to the current time b) only call `next_backoff` when we want to resend a message Within the sans-IO design of `connlib`, time-related functions are handled within `handle_timeout` which is being passed a `now: Instant` parameter. Instead of ticking over to the next backoff, what we need from our backoff module are answers to the questions: - Is the backoff expired? - When should the next retry happen? - What is the current waiting interval? In addition, we want the backoff module to "tick over" to the next trigger when the time passes the current one, i.e. we want to issue the command: "This is the current time, update your internal state." By re-implementing this ourselves, we can avoid this additional state tracking of `last_now`, thus simplifying the implementation.
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:
- Ensure the binary you are profiling is compiled with the
releaseprofile. sudo perf record -g --freq 10000 --pid $(pgrep <your-binary>).- Run the speed test or whatever load-inducing task you want to measure.
sudo perf script > profile.perf- 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.