Available Slot Occupancy

What does this counter show?

This counter represents the occupancy of the shader engine's available slots. Tasks in these slots may be ready for execution or may be resolving data dependencies. When an active slot becomes vacant, the shader engine will populate it with a ready task from the available slot list.

What does a high value mean?

A high percentage indicates that there are a sufficient number of tasks in the pipeline to feed the active slots. A low percentage may indicate:

  • Register pressure: Each occupant task utilises register space for its inputs. If a large amount of registers are required for the occupant tasks (i.e. register pressure is high), there may not be enough space available to schedule tasks into vacant slots.

  • ISP bottlenecked: If the pipeline is bottlenecked by the ISP, there may be an insufficient number of tasks sent to the shader engine to populate all available slots.