I built SceneTrace, a free Blender extension for tracking scene performance over time.
The idea came from a simple problem:
A scene gets slower, but what actually caused it?
SceneTrace lets you create a performance baseline while the scene is running well, then re-test it later after the scene has changed.
It compares the measurements and helps narrow down which changes are associated with the slowdown.
What it does
- Creates calibrated interactive performance baselines
- Re-tests the current scene against an existing baseline
- Detects performance regressions
- Compares median, P95, and worst frame times
- Shows measured contributor evidence directly inside Blender
- Keeps the analysis local
The goal is not just to tell you that a scene is slow, but to give you evidence for investigating why it became slower.
Example workflow
- Create a baseline while your scene performs normally.
- Continue working on the scene.
- Add geometry, modifiers, materials, collections, etc.
- Notice that viewport performance has degraded.
- Run SceneTrace again.
- Compare the new measurements with the baseline and inspect the detected regression and contributor evidence.
CLI and CI
SceneTrace also includes a Rust-based CLI.
That means performance comparisons can be run outside the Blender UI and integrated into automated workflows.
For example, a studio or technical artist could use SceneTrace in CI to detect scene-performance regressions as project files change instead of discovering them only after artists notice that a scene has become slow.
Free and open source
SceneTrace is free and open source.
GitHub:
Requires Blender 4.2 or newer.
Feedback is very welcome, especially from people working with larger or performance-sensitive Blender scenes. I’d be interested to hear what kinds of scene slowdowns are hardest for you to diagnose today.