Profiling

Godot-Bevy, together with Bevy native, supports several methods of profiling. In this article, we'll discuss using Tracy. We recommend you read Bevy's profiling doc first.

Instructions

  • In your Cargo.toml, under dependencies add necessary tracy dependencies, e.g.:
[dependencies]
tracing = "0.1"
tracing-tracy = { version = "0.11.4", default-features = false, features = [
  "enable",
  "manual-lifetime",
  "ondemand",
  "broadcast",       # announce presence
], optional = true }
  • In your Cargo.toml, under features add a trace_tracy (feel free to rename it):
[features]
trace_tracy = ["dep:tracing-tracy", "godot-bevy/trace_tracy"]
  • Install Tracy, see https://github.com/bevyengine/bevy/blob/main/docs/profiling.md for details on picking the correct version to install. As of July 2025, you need Tracy Profiler 0.12.2, which you can obtain from The official site. Alternatively, you can use the zig-built version, which makes it much easier to build c binaries across platforms, see https://github.com/allyourcodebase/tracy
  • Once built, run the Tracy Profiler (tracy-profiler), and hit the Connect button so it's listening/ready to receive real time data from your game
  • Build your game. You can use either dev or release, both work, though we recommend release since you'll still get symbol resolution and your profiling numbers will reflect what you're actually shipping in addition to being much faster than a dev build.
  • Run your game, you should see real time data streaming into the Tracy profiler GUI.
  • For a complete example of this in action, see our Bevy Boids example

Notes

If you see the following warning:

#![allow(unused)]
fn main() {
warning: unexpected `cfg` condition value: `trace_tracy`
}

after ugprading to Godot Bevy 0.9, add the following at the top of the problematic file (wherever you use the bevy_app macro):

#![allow(unused)]
#![allow(unexpected_cfgs)] // silence potential `tracy_trace` feature config warning brought in by `bevy_app` macro
fn main() {
}