Maximizing Service Reliability in Distributed Computing Systems with Random Node Failures: Theory and Implementation

• Published in: IEEE transactions on parallel and distributed systems Vol. 21; no. 10; pp. 1531 - 1544
• Main Authors: Pezoa, J E, Dhakal, S, Hayat, M M
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2010; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Communication networks; Computer networks; Computer simulation; Difference equations; Distributed computing; Distributed control; Distributed processing; Load balancing; Load balancing (computing); Mathematical analysis; Monte Carlo methods; queuing theory; reliability; Reliability theory; Renewal theory; Shipping industry; Stochastic processes; Stochastic systems; Stochasticity; Studies; System performance; Telecommunication network reliability; Theory; Uncertainty
• ISSN: 1045-9219; 1558-2183
• DOI: 10.1109/TPDS.2010.34

In distributed computing systems (DCSs) where server nodes can fail permanently with nonzero probability, the system performance can be assessed by means of the service reliability, defined as the probability of serving all the tasks queued in the DCS before all the nodes fail. This paper presents a rigorous probabilistic framework to analytically characterize the service reliability of a DCS in the presence of communication uncertainties and stochastic topological changes due to node deletions. The framework considers a system composed of heterogeneous nodes with stochastic service and failure times and a communication network imposing random tangible delays. The framework also permits arbitrarily specified, distributed load-balancing actions to be taken by the individual nodes in order to improve the service reliability. The presented analysis is based upon a novel use of the concept of stochastic regeneration, which is exploited to derive a system of difference-differential equations characterizing the service reliability. The theory is further utilized to optimize certain load-balancing policies for maximal service reliability; the optimization is carried out by means of an algorithm that scales linearly with the number of nodes in the system. The analytical model is validated using both Monte Carlo simulations and experimental data collected from a DCS testbed.