FPZL Schedulability Analysis
Source: University of York
This paper presents the FPZL scheduling algorithm for multiprocessor real-time systems. FPZL is similar to global fixed priority pre-emptive scheduling; however, whenever a task reaches a state of zero laxity it is given the highest priority. FPZL is a minimally dynamic algorithm, in that the priority of a job can change at most once during its execution. Polynomial time and pseudo-polynomial time sufficient schedulability tests are derived for FPZL. These tests are then improved by computing upper bounds on the amount of execution that each task can perform in the zero laxity state.