Events in a distributed computation have been implicitly modeled in the literature in the isolated contexts of various applications. This paper presents a unifying framework for expressing and analyzing events at various levels of atomicity in a distributed computation. In the framework, events at any level of atomicity are defined and composed in terms of events at a finer level of atomicity using hierarchical views of the distributed computation. We identify and prove three properties that are satisfied by each level of atomicity. Results based on these properties that hold for any one level of atomicity apply to all levels of atomicity. The properties also show that the global states at the various levels of atomicity correspond to embedded lattices of global states, thereby providing different abstract views of the same computation.
This is a revised and expanded version of the paper by the same title that appears in the Proc. EuroPar'96, Lecture Notes in Computer Science, vol. 1123, Springer, Berlin, 1996, pp. 496–505.
