Solving layered queueing networks of large client-server systems with symmetric replication

Abstract

Large distributed client-server systems often contain subsystems which are either identical to each other, or very nearly so, and this simplifies the system description for planning purposes. These replicated components and subsystems all have the same workload and performance parameters. It is known how to exploit this symmetry to simplify the solution of some kinds of performance models, using state aggregation in Markov Chains. This work considers the same problem for layered queueing models, using mean value analysis. The mean values are found for each group of replicas just once, and then are inserted appropriately into the solution of the system as a whole. An algorithm has been implemented in the Layered Queueing Network Solver (LQNS), including approximations to deal with interactions among the replicas, and is evaluated for accuracy and for efficiency. The resulting solver is insensitive (in time of solution) to the number of replicas in a group, and can efficiently calculate waiting times and throughputs for systems with tens of thousands of nodes and processes.

A Simplified Solution of a PEPA Model of Kerberos Protocol

“…An idea of iterative solution from layered queueing network [8] is proposed to solve the PEPA model of Kerberos protocol with heterogeneous environment; this remains a issue for further investigation.…”

Capacity Planning and Allocation for Web‐Based Applications

“…Rolia and Sevcik (1995) have used LQN and have developed the method of layers (MOL) to estimate the performance of distributed applications. Omari, Franks, Woodside, and Pan (2005) have developed a solution procedure for LQN with replicated subsystems to model large client-server systems with several identical subsystems. Omari, Franks, Woodside, and Pan (2006) extended this methodology to consider parallel subsystems in the network.…”

Model-Driven Web Engineering Performance Prediction with Layered Queue Networks

“…LQNs are one of the most adopted technique and have been efficiently applied also in other related contexts, like ERP applications [10] heavily adopting multithreading and multi-core architectures, in the early phases of Software Product Lines [12], in the optimization of the deployment of multiple Web applications on a cloud [8], with replicated components [9], where LQN based approaches scale very well.…”