A framework for modelling web-based applications with resource locking

The performance of web-based applications depends on the interaction among various entities such as web servers, application servers, and databases. One such critical interaction is resource locking that occurs when an application server sends a request to an external server and remains 'locked' until it returns. This increases the effective load on the system and has implications on quality of service. We model a web-based system with resource locking as a queuing network, validate our model and assumptions and compare our results with simulation. Our framework can serve as a building block for developing analytical models of complex web-based applications.