Documentation

Unity Engine


User Manual

Script Reference

Unity Engine


Optimize physics performance

Optimize physics system performance in the Unity Editor.
Read time 2 minutesLast updated 12 days ago

Optimize physics system performance in the Unity Editor.
Use the guidance in these pages to optimize the physics system so you can maintain your target frame rate and ensure smooth, responsive gameplay. The instructions in these pages address issues identified by Unity Editor diagnostic tools. Before you apply the optimizations described in the documentation in this section and throughout your development, you must be familiar with these diagnostic tools:
  • The Unity Profiler: The Profiler is the primary tool to measure CPU performance. The Profiler helps identify bottlenecks in your project, particularly in areas such as
    Physics.FixedUpdate
    and
    Physics.Simulate
    , and in its detailed breakdowns of physics phases such as broad phase and narrow phase processing. To open the Profiler window, go to Window > Analysis > Profiler.
  • The Memory Profiler: Use the Memory Profiler to identify and optimize memory allocations caused by physics operations, such as excessive
    RaycastHit
    arrays or frequent collision data creation. You can use this information to reduce your garbage collection overhead.
  • The Physics Debug window: Use this tool to visually diagnose physics-related performance issues. It displays collision shapes, contacts, broad phase bounding boxes, and Rigidbody component sleep states. This helps you identify areas like overly complex colliders, unnecessary interactions, or objects failing to sleep, all of which contribute to performance bottlenecks. To open the Physics Debug window, select Window > Analysis > Physics Debug.

Topic

Description

Optimize the physics system for CPU usageOptimize Unity's physics system's CPU usage by adjusting simulation frequency, managing colliders, and configuring Rigidbody components.
Optimize the physics system for memory usageOptimize Unity's physics system's memory usage by controlling collision callbacks and optimizing physics queries.
Understand physics performance issuesUnderstand performance issues related to physics in your application.

Additional resources