Towards parsimonious resource allocation in context-aware n-version programming

Adopting classic redundancy-based fault-tolerant schemes in highly dynamic distributed computing systems does not necessarily result in the anticipated improvement in dependability. This primarily stems from statically predefined redundancy configurations employed within many classic dependability strategies, which as well known may negatively impact the schemes´ overall effectiveness. In this paper, a novel dependability strategy is introduced encompassing advanced redundancy management, aiming to autonomously tune its internal configuration in function of disturbances observed. Policies for parsimonious resource allocation are presented thereafter, intent upon increasing the scheme´s cost effectiveness without breaching its availability objective. Our experimentation suggests that the suggested solution can achieve a substantial improvement in availability, compared to traditional, static redundancy strategies, and that tuning the adopted degree of redundancy to the actual observed disturbances allows unnecessary resource expenditure to be reduced, therefore enhancing cost-effectiveness.