# maxSubStepCount

> The maximum number of simulation sub-steps allowed per-frame when simulation sub-stepping is enabled.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine](/engine/6000.5/script-reference/unityengine.md)
* **Assembly:** UnityEngine.Physics2DModule

```csharp
public static int maxSubStepCount { get; set; }
```

### Remarks

When simulation sub-stepping is enabled with [Physics2D.useSubStepping](/engine/6000.5/script-reference/unityengine/physics2d/usesubstepping.md), this property is used to control the maximum number of simulation sub-steps that will occur.

When sub-stepping occurs, multiple simulation sub-steps will happen. Running too many simulation sub-steps will result in poor performance. Indeed, the reason that sub-stepping is used is because of a low frame-rate situation so care needs to be taken to ensure that the situation is not made worse by running too many simulation sub-steps.

If the required number of simulation sub-steps exceed the allowed [maximum](/engine/6000.5/script-reference/unityengine/physics2d/maxsubstepcount.md) and the frame-rate cannot be divided into updates at or higher than the [Physics2D.minSubStepFPS](/engine/6000.5/script-reference/unityengine/physics2d/minsubstepfps.md) then only the maximum number of sub-steps are used. This results in time being "lost" in the simulation with the benefit that the cost of sub-stepping is restrained. The total amount of "lost" time can be read from [PhysicsScene2D.subStepLostTime](/engine/6000.5/script-reference/unityengine/physicsscene2d/substeplosttime.md). The number of simulation sub-steps taken in the last simulation step can be read from [PhysicsScene2D.subStepCount](/engine/6000.5/script-reference/unityengine/physicsscene2d/substepcount.md). The cost of this should be monitored with the Unity Profiler using the Physics 2D Module.

Additional Resources: [Physics2D.useSubStepping](/engine/6000.5/script-reference/unityengine/physics2d/usesubstepping.md), [Physics2D.minSubStepFPS](/engine/6000.5/script-reference/unityengine/physics2d/minsubstepfps.md), [PhysicsScene2D.subStepCount](/engine/6000.5/script-reference/unityengine/physicsscene2d/substepcount.md) and [PhysicsScene2D.subStepLostTime](/engine/6000.5/script-reference/unityengine/physicsscene2d/substeplosttime.md).