Exploiting Sporadic Servers to provide Budget Scheduling for ARINC653 based Real-Time Virtualization Environments
Matthias Beckerta, Kai Björn Gemlaub and Rolf Ernstc
Institute of Computer and Network Engineering, TU Braunschweig, Germany.
abeckert@ida.ing.tu-bs.de
bgemlau@ida.ing.tu-bs.de
cernst@ida.ing.tu-bs.de
ABSTRACT
Virtualization techniques for embedded real-time systems typically employ TDMA scheduling to achieve temporal isolation among different virtualized partitions. Due to the fixed TDMA schedule, worst case response times for IRQs and tasks are significantly increased. Recent publications introduced slack based IRQ shaping to mitigate this problem. While providing better response times for IRQs, those mechanisms neither improve task timings nor provide a work conserving scheduling. In order to provide such capabilities while still providing temporal isolation, we introduce a method based on the well known sporadic server model. In combination with a proposed budget scheduler the system is able to schedule a TDMA based configuration while providing better response times and the same amount of temporal isolation. We show correctness of the approach and evaluate it in a hypervisor implementation.
