Efficient evaluation of design choices, in terms of selection of algorithms to be implemented as hardware or software, and finding an optimal hw/sw design mix is an important requirement in the design flow of Embedded Systems. Time-to-market, faster upgradability and flexibility are some of the driving points to put increasing amounts of functionality as software executed on general purpose processing elements. In this scenario, dividing a monolithic task into multiple interacting tasks, and scheduling them on limited processing elements has become very important for a system designer. This paper presents an approach to model time-slice based task schedulers in the designs where the performance estimate of hardware and software models is less than timeslice accurate. The approach aims to increase the simulation efficiency of designs modeled at system level. We used Metropolis [1] as our codesign environment.