Resource Availability Characteristicsand Node Selection in CooperativelyShared Computing Platforms

The focus of our work is on studying the resource availability characteristics of large-scale, cooperatively pooled, shared computing platforms. Our focus is on platforms in which resources at a node are allocated to competing users on fair-share basis, without any reserved resource capacities for any user, and there is no platform-wide resource manager for the placement of users on different nodes. The users independently select nodes for their applications. Our study is focused on the PlanetLab system which exemplifies such platforms. The goal of our study is to develop heuristics based on the observed resource availability characteristics for selecting nodes for deploying applications. Our approach uses the notion of eligibility period, which represents a contiguous duration for which a node satisfies a given resource requirement. We study the characteristics of the eligibility periods of Planetlab nodes for various resource capacity requirements. Based on this study we develop heuristics for identifying nodes that are likely to satisfy a given requirement for long durations. We also develop an online model for predicting the idle resource capacity that is likely to be available on a node over a short term. We evaluate and demonstrate the performance benefits of the node selection techniques and the prediction model using the PlanetLab node utilization data traces collected at different intervals over an extended period of several months.