The Impact of Workload Variability on Load Balancing Algorithms

The workload on a cluster system can be highly variable, increasing the difficulty of balancing the load across its nodes. The general rule is that high variability leads to wrong load balancing decisions taken with out-of-date information and difficult to correct in real-time during applications execution. In this work the workload variability is studied from the perspective of the load balancing performance, focusing on the design of algorithms capable of dealing with this variability. In this paper an exhaustive analysis is presented to help users and administrators to understand if their load balancing mechanisms are sensitive to variability and to what degree. Furthermore, solutions to deal with variability in load balancing algorithms are proposed and their utilization is exemplified on a real load balancing algorithm.