Instance Property


A value that indicates the system pressure cost of the current session configuration.


var systemPressureCost: Float { get }


The session’s system pressure cost value, ranging from 0.0 to 1.0, indicates the cost of running the current session configuration. When the value exceeds 1.0, the capture session cannot run sustainably, but it may be able to run briefly before stopping. While the session is running in an unsustainable configuration, you may monitor the device’s systemPressureState and reduce pressure by reducing the frame rate, throttling your use of the GPU, and so on.

When the session reaches a critical system pressure state, it temporarily shuts down, and your app receives an AVCaptureSessionWasInterrupted notification indicating the reason your session stopped. When system pressure is alleviated, the session interruption ends.

See Also

Managing Resources

var hardwareCost: Float

A value that indicates the percentage of the session’s available hardware budget currently in use.