CPU Utilization Graph
The CPU Utilization graph illustrates the level of concurrency in an application over time. The X-axis represents the duration of the application, and the y-axis represents the number of logical cores on the system. The graph does not show which specific core is active at any given time. For example, if two cores are each running at 50% capacity for a given time period, then this view will show one logical core being utilized.
Green indicates the consumption of the logical cores in the system by the profiled application.
Yellow indicates the consumption of logical cores by other processes on the system. A high percentage of yellow in the graph indicates that the system is heavily loaded by other processes and that your process is likely to be pre-empted by them. To reduce the consumption of logical cores by other processes, reduce the number of them running on the system.
Red indicates the consumption of logical cores by the system process. You cannot directly control this, but it is useful to know when it is occurring because it can affect the availability of logical cores for your process.
Grey indicates the availability of unused logical cores on the system. Those cores are available for your process if you can find more opportunities for parallelism. In all cases, hovering the mouse pointer over an area of interest produces a tooltip which identifies that particular part of the graph.