Offline Operating System-Based Diagnostics

When diagnostics are written on top of an operating system, the diagnostics can rely on the resources of the OS (for example, process scheduling) to allow simultaneous testing of multiple components. However, some direct control of the components might be lost. That is, the OS enforces encapsulation of hardware resources, as necessary, to prevent access by the diagnostics to ensure reliable system behavior.

Further, since the OS inherently manages system resources, exercisers can be built using the OS that can test multiple subsystems simultaneously.