This disclosure pertains to systems, methods, and computer readable media for utilizing an unused hardware thread of a multi-core microcontroller of a graphical processing unit (GPU) to gather sampling data of commands being executed by the GPU. The multi-core microcontroller may include two or more hardware threads and may be responsible for managing the scheduling of commands on the GPU. In one embodiment, the firmware code of the multi-core microcontroller which is responsible for running the GPU may run entirely on one hardware thread of the microcontroller, while the second hardware thread is kept in a dormant state. This second hardware thread may be used for gathering sampling data of the commands run on the GPU. The sampling data can be used to assist developers identify bottlenecks and to help them optimize their software programs.