On the minimal characterization of the rollback-dependency trackability property

An efficient checkpointing protocol for the minimal characterization of operational rollback-dependency trackability

“…The continuity of the RDT property under RDT protocols has lead us to introduce the concept of leftdoubling [7]. A C-path µ belongs to a consistent cut C if the reception of the last message of µ belongs to C. A Z-path ζ belongs to C if all causal components of ζ belong to C. …”

“…These assumptions imply that the RDT property must be enforced continuously during the progress of a distributed computation. Based on this observation, we introduce a property called operational RDT and we describe a checkpointing protocol, called RDT-Minimal, that breaks only the minimal set of non-trackable dependencies necessary to enforce operational RDT [7]. According to Tsai [14], this protocol must present exactly the same behavior (must induce forced checkpoints at the same execution points) as the one proposed by Baldoni, Helary, Mostefaoui, and Raynal [1,3].…”

Optimal Asynchronous Garbage Collection for RDT Checkpointing Protocols

“…This ensures that all checkrag replacements point dependencies are causal and can be tracked by using transitive dependency vectors. RDT checkpointing protocols rely on the model we presented and ensure that the CCP of any consistent cut of the distributed computation is RD-trackable [9]. Therefore, henceforth we assume that all the checkpoint and communication patterns are RD-trackable and we omit this condition in statements of definitions, lemmas and theorems.…”

“…Initially, p i eliminates the checkpoints rolled back and calculates the new dependency vector DV (lines 4-6). After that, p i finds for every process p f , based on Theorem 1, the stable checkpoint that must be retained by p i because of p f and updates UC [f ] accordingly (lines [9][10][11][12][13][14] …”

“…Garcia et al [10] and Baldoni et al [3] presented protocols that take fewer forced checkpoints than the protocols presented by Wang [21]. Important results in this context are related to the minimal visible characterization of the RDT property [4,9], which gives the strongest condition to be tested for taking forced checkpoints in order to ensure RDT. Nevertheless, Tsai et al [20] showed that strong conditions not always translate into a fewer number of forced checkpoints during the whole execution.…”