Autonomic thread scaling library for QoS management

Over the last years embedded system industry faced a revolution thanks to the introduction of multicores and heterogeneous devices. The availability of these new platforms opens new paths for these devices that can be nowadays used for more high demand tasks, exploiting the parallelism made available by the muticore processors. Nonetheless the progresses of the HW technology are not backed up by improvements of the SW side, and runtime mechanisms to manage resource allocation and contention on resources are still lacking the proper effectiveness. This paper tackles the problem of dynamic resource management from the application point of view and presents a user space library to control application performance. The control knob exploited by the library is the possibility of scaling the number of threads used by an application and seamlessly integrates with OpenMP. A case study illustrates the benefits that this library has in a classic embedded system scenario, introducing an overhead of less than 0.5%.