Previous system scheduling approaches have focused primarily on system-level abstractions for scheduling decision functions and the mechanisms used to implement them. This paper introduces a new abstraction called group scheduling that focuses primarily on the progress of application-level computations and on organizing system-level scheduling abstractions to ensure that progress.

This paper makes three contributions to system scheduling research. First, it defines a model for group scheduling that augments and complements hierarchical scheduling models. Second, it describes how a computation?s progress semantics can be mapped to scheduling mechanisms at the operating system and middleware levels. Third, it presents preliminary empirical studies of the performance of group scheduling in a realistic system environment.