More Properties of Communication-Induced Checkpointing Protocols with Rollback-Dependency Trackability

Rollback-Dependency Trackability (RDT) is a property stating that all rollback dependencies between local checkpoints are on-line trackable using a transitive dependency vector. In this paper, we introduce some properties of communication-induced checkpointing protocols possessing the RDT property. First, we demonstrate that wherever an RDT protocol detects a PCM-path in the checkpoint and communication pattern associated with a distributed computation, it can also detect an EPSCM-path there. Moreover, if this detected PCM-path is non-visibly doubled, its corresponding EPSCMpath is also non-visibly doubled. Next, we go on to prove that if an RDT protocol breaks all EPSCM-cycles and non-visibly doubled EPSCM-paths, it breaks all visibly doubled EPSCM-paths as well. From these results, we find that some RDT protocols actually have the same behavior for all possible patterns. Furthermore, we also construct patterns to show that a few RDT protocols are incomparable in terms of the number of forced checkpoints. Last but not least, we discuss a simulation study to verify our previous theoretical results.