Performance Analysis of the Active Object Pattern in Middleware

A number of enterprises are turning towards the Service Oriented Architecture (SOA) approach for their systems due to the number of benefits it offers. A key enabling technology for the SOA-based approach is middleware, which comprises of reusable building blocks based on design patterns. These building blocks can be configured in numerous ways and the configuration options of a pattern can have a profound impact on system performance. A performance analysis methodology which can be used to assess this influence at design time can guide the selection of patterns and their configuration options and thus alleviate the possibility of performance problems arising later in the life cycle. This paper presents a model-based performance analysis methodology for a system built using the Active Object (AO) pattern. The AO pattern is chosen because it lies at the heart of an important class of producer/consumer and publish/subscribe systems. Central to the methodology is a queuing model which captures the internal architecture of an AO-based system. Using an implementation of the queuing model in CSIM, we illustrate the value of the methodology to guide the selection of configuration and provisioning options for a stock broker system.