[IJHPSA] Resilience to Churn of a Peer-to-Peer Evolutionary Algorithm

In this paper we analyse the resilience of a Peer-to-Peer (P2P) Evolutionary Algorithm (EA) subject to the following dynamics: computing nodes acting as peers leave the system independently from each other causing a collective effect known as churn. Since the P2P EA has been designed to tackle large instances of computationally expensive problems, we will assess its behaviour under these conditions, by performing a scalability analysis in five different scenarios using the Massively Multimodal Deceptive Problem as a benchmark.In all cases, the P2P EA reaches the success criterion without a penalty on the runtime. We show that the key to the algorithm resilience is to ensure enough peers at the beginning of the experiment; even if some of them leave, those that remain contain enough information to guarantee a reliable convergence.