Examples are described here that can be used to allocate commands from multiple sources to performance by one or more segments of a processing device. For example, a processing device can be segmented into multiple portions and each portion is allocated to process commands from a particular source. In the event a single source provides commands, the entire processing device (all segments) can be allocated to process commands from the single source. When a second source provides commands, some segments can be allocated to perform commands from the first source and other segments can be allocated to perform commands from the second source. Accordingly, commands from multiple applications can be executed by a processing unit at the same time.