Title: Resilience to churn of a peer-to-peer evolutionary algorithm

Authors: J.L.J. Laredo, P.A. Castillo, A.M. Mora, J.J. Merelo, C. Fernandes

Addresses: Department of Architecture and Computer Technology, University of Granada, Periodista Daniel Saucedo, 18071 Granada, Spain. ' Department of Architecture and Computer Technology, University of Granada, Periodista Daniel Saucedo, 18071 Granada, Spain. ' Department of Architecture and Computer Technology, University of Granada, Periodista Daniel Saucedo, 18071 Granada, Spain. ' Department of Architecture and Computer Technology, University of Granada, Periodista Daniel Saucedo, 18071 Granada, Spain. ' LASEEB-ISR/IST, University of Lisbon, Av. Rovisco Pais 1049-001 Lisbon, Portugal

Abstract: 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.

Keywords: peer-to-peer computing; P2P computing; evolutionary algorithms; fault tolerance analysis; scalability; evolvable agents; churn.

DOI: 10.1504/IJHPSA.2008.024210

International Journal of High Performance Systems Architecture, 2008 Vol.1 No.4, pp.260 - 268

Published online: 29 Mar 2009 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article