Performance Tuning

Identify Bottleneck

Identifying the bottleneck of performance problem is the first step of tuning. Chapter 2 of VR Rendering Performance guideline aims developers to use tool for preliminary analysis.

Improve Performance and Quality

1. XR Performance and Profiling: Tools and strategies provided by UE5.
2. Foveated Rendering: Trade-off between content frame peripheral quality and GPU resources.
   • For most of the cases, the Fixed Mode is a nice starting point. You can improve GPU performance with barely noticeable visual quality loss in periphery.
   • If your rendering scene has no head locked objects, and the FPS can not reach refresh rate. You may try the Dynamic Mode for further performance improvement.
   • Enabling foveated rendering feature incurs a fixed GPU performance cost, which can vary between 1% to 6% depending on the size of the eye buffer. When using a simple shader in the scene, the performance gain from saving resources might be lower than the fixed GPU performance cost, resulting in a performance drop. Therefore, it is advisable to enable or disable the feature based on your specific requirements and performance considerations.
3. Display Refresh Rate: Higher refresh rates offer smoother visuals, but come at the cost of increased system load. Conversely, lower refresh rates reduce system load, but result in less smooth visuals.
4. Passthrough Configuration: Better quality or higher image rates deliver smoother visuals but increase system load. Conversely, lower quality or reduced image rates ease system load but compromise visual smoothness.

Please access VR Rendering Performance guideline for more tuninng tips

Tools

These tools provide deep insights into system behavior and application performance, helping developers identify and resolve bottlenecks effectively.

• Android Systrace

  Android Systrace is a low overhead but powerful tool that can analyze performance.
  To learn more, please go to System trace on the command line | Android Developers.

• Snapdragon Profiler

  Snapdragon Profiler is a comprehensive performance profiling tool for Snapdragon-based devices. Enabling optimization for better efficiency and stability.
  To learn more, please go to Snapdragon Profiler | Qualcomm Developers.