Analysing Evolution of Work and Load

Evolution of work and load is required for investigating elasticity and cost-efficiency of cloud computing applications as well as their underlying architecture. Existing modelling environments have fixed load and work, therefore rendering model-and-analyse approaches infeasible for such applications. This deficiency particularly leads to high risks that applications will violate their service level objectives. Therefore, this article describes how we can model and analyse the evolution of both work and load. We have created a corresponding meta model for usage evolution, and describe how we have integrated our meta model with Palladio, a common model-and-analyse environment. To model evolution we use the Descartes Load Intensity Model (DLIM). DLIM is coupled with the scenario model in the Palladio Component Model (PCM). We illustrate evolution of both work and load within Palladio simulations using a simple image server example.