Enhancing Dependability of Cooperative Applications in
François J.N. Cosquer, Pedro Antunes and Paulo Veríssimo
From Dependable Computing - EDCC-2, volume 1150 of Lecture Notes in
Computer Science, chapter 6, pp.335-352.
This paper presents a pragmatic approach to providing partition
processing system support for cooperative applications. A method for
specifying and programming application-level partition processing
strategies is described. The system support is based on a partition
typing mechanism which allows the application programmer to model the
relative importance of partitions. This is combined with a split/merge
rules configuration table through which the partition processing
strategy is defined. In the context of cooperative application
semantics, our approach combines the correctness of the pessimistic,
and the availability of the optimistic approaches for data management
in partitionable environments. The paper focuses on the practical
issues linked with, firstly, the specification, and secondly, the
support at runtime, of the partition processing strategies. This
approach is relevant in the context of large-scale asynchronous
distributed systems such as the Internet, which, as a result of
current technology and topology, are inevitably prone to
partitions. Examples are given, illustrating how the partition support
is used and combined with new feedback techniques in order to
implement more robust cooperative environments.
extended report (gzip postscript).