3e6094af8d
The default send and receive buffer sizes on Linux are too small (only ~200 KB). Checking `nstat` after an iperf run revealed that the number of dropped packets in the first interval directly correlates with the number of receive buffer errors reported by `nstat`. We already try to increase the send and receive buffer sizes for our UDP socket but unfortunately, we cannot increase them beyond what the system limits them to. To workaround this, we try to set `rmem_max` and `wmem_max` during startup of the Linux headless client and Gateway. This behaviour can be disabled by setting `FIREZONE_NO_INC_BUF=true`. This doesn't work in Docker unfortunately, so we set the values manually in the CI perf tests and verify after the test that we didn't encounter any send and receive buffer errors. It is yet to be determined how we should deal with this problem for all the GUI clients. See #10350 as an issue tracking that. Unfortunately, this doesn't fix all packet drops during the first iperf interval. With this PR, we now see packet drops on the interface itself.
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.