The Möbius Execution Policy ∗ Daniel

Möbius is an extensible framework and tool for performance and dependability modeling, and supports multiple modeling formalisms and solvers. As a framework, Möbius must be sufficiently general to capture the various formalism behaviors. Specifically, the Möbius execution policy must be flexible enough to accommodate the execution policies of all formalisms implemented in the framework. We know of no existing execution policy which is capable of doing this and meeting the many other goals of the framework. We present the Möbius execution policy that addresses these needs. In developing the policy, we have generalized the various preemption policies and made all aspects of the execution policy state-dependent, which has never before been considered. Because all aspects may be state-dependent, we also had to relax the assumption that work proceeds at a constant rate; this is also novel. Finally, we show that within the context of Möbius, the extra structure and overhead needed to implement a particular behavior can largely be avoided except when that behavior is present in a model.