PROJECT TITLE :

Two-Phase Low-Energy N-Modular Redundancy for Hard Real-Time Multi-Core Systems

ABSTRACT:

This paper proposes an N-modular redundancy (NMR) technique with low energy-overhead for laborious real-time multi-core systems. NMR is well-fitted to multi-core platforms as they provide multiple processing units and low-overhead communication for voting. However, it can impose considerable energy overhead and hence its energy overhead should be controlled, which is the first thought of this paper. For this purpose the system operation can be divided into 2 phases: indispensable section and on-demand phase. In the indispensable phase solely [*fr1]-and-one copies for each task are executed. When no fault happens throughout this section, the results should be identical and hence the remaining copies are not needed. Otherwise, the remaining copies should be executed in the on-demand section to perform an entire majority voting. During this paper, for such a two-part NMR, an energy-management technique is developed where two new ideas have been thought-about: i) Block-partitioned scheduling that enables parallel task execution throughout on-demand part, thereby leaving a lot of slack for energy saving, ii) Pseudo-dynamic slack, that results when a task has no faulty execution throughout the indispensable part and hence the time which is reserved for its copies in the on-demand phase is reclaimed for energy saving. The energy-management technique has an off-line half that manages static and pseudo-dynamic slacks at style time and an online part that mainly manages dynamic slacks at run-time. Experimental results show that the proposed NMR technique provides up to twenty nine percent energy saving and is half-dozen orders of magnitude higher reliable as compared to a recent previous work.