A model of pilot-job resource provisioning on production grids
Pilot-job systems emerged as a computation paradigm to cope with the heterogeneity of large-scale production grids, greatly reducing fault ratios and middleware overheads. They are now widely adopted to sustain the computation of scientific applications on such platforms. However, a model of pilot-job systems is still lacking, making it difficult to build realistic experimental setups for their study (e.g. simulators or controlled platforms). The variability of production conditions, background loads and resource characteristics further complicate this issue. This paper presents a model of pilot-job resource provisioning. Based on a probabilistic modeling of pilot submission and registration, the number of pilots registered to the application host and the makespan of a divisible-load application are derived. The model takes into account job failures and it does not make any assumption on the characteristics of the computing resources, on the scheduling algorithm or on the background load. Only a minimally invasive monitoring of the grid is required. The model is evaluated in production conditions, using logs acquired on a pilot-job server deployed in the biomed virtual organization of the European Grid Infrastructure. Experimental results show that the model is able to accurately describe the number of registered pilots along time periods ranging from a few hours to a few days and in different pilot submission conditions.
production grids pilot-job systems probabilistic modeling