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arXiv · 2407.06968

An automata-based approach for synchronizable mailbox communication

Romain Delpy·Anca Muscholl·Grégoire Sutre
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Abstract

We revisit finite-state communicating systems with round-based communication under mailbox semantics. Mailboxes correspond to one FIFO buffer per process (instead of one buffer per pair of processes in peer-to-peer systems). Round-based communication corresponds to sequences of rounds in which processes can first send messages, then only receive (and receives must be in the same round as their sends). A system is called synchronizable if every execution can be re-scheduled into an equivalent execution that is a sequence of rounds. Previous work mostly considered the setting where rounds have fixed size. Our main contribution shows that the problem whether a mailbox communication system complies with the round-based policy, with no size limitation on rounds, is Pspace-complete. For this we use a novel automata-based approach, that also allows to determine the precise complexity (Pspace) of several questions considered in previous literature.

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Romain Delpy, Anca Muscholl, Grégoire Sutre. 2024-07-09. An automata-based approach for synchronizable mailbox communication. https://doi.org/10.46298/lmcs-22(2%3A24)2026

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