Pfair scheduling improvement to reduce interprocessor migrations

Dalia Aoun (1) , Anne-Marie Déplanche (1) , Yvon Trinquet (1)

1 IRCCyN - Institut de Recherche en Communications et en Cybernétique de Nantes

Proportionate-fair (Pfair) scheduling is a particulary promising global scheduling technique for multiprocessor systems. Actually three Pfair scheduling algorithms have been proved optimal for scheduling periodic, sporadic and rate-based tasks on a real-time multiprocessor. However, task migration is unrestricted under Pfair scheduling. In the worst case, a task may be migrated each time it is scheduled. To correct this problem, we propose to complement initial Pfair scheduling algorithm by some heuristics that strive to minimize the total number of migrations. Experimental simulations are presented to evaluate and compare the proposed heuristics and we show that the number of migrations can be substantially reduced by adding these simple rules.

Domaines: Systèmes embarqués

Dalia Aoun, Anne-Marie Déplanche, Yvon Trinquet. Pfair scheduling improvement to reduce interprocessor migrations. 16th International Conference on Real-Time and Network Systems (RTNS 2008), Isabelle Puaut, Oct 2008, Rennes, France. ⟨inria-00336513⟩