Impediments to Analytical Modeling of Multi-Tiered Web Applications

Service providers hosting multi-tiered applications require accurate analytical models of the applications they will host for different system management activities, such as capacity planning, configuration management, cost analysis and feedback control. Due to the complexity of real world scenarios, developing accurate analytical models is hard. This paper presents the commonly faced challenges in developing these analytical models that stem from real-world issues, such as excessive system activity, presence of multiple cores or processors, and concurrency management. Presence of multi-tiered applications further compounds the challenges faced. We sketch preliminary ideas based on application-specific and/or domain-specific modeling techniques to overcome these limitations.