Due to the dynamic properties of autonomous resource providers, the coupling of independent services as a Grid transaction may abort with inconsistency. In many situations people would resort to compensation actions t...
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Due to the dynamic properties of autonomous resource providers, the coupling of independent services as a Grid transaction may abort with inconsistency. In many situations people would resort to compensation actions to regain consistency;consequently there comes the issue of compensation-cost. To handle such an issue, for the first time we set up a costing model for the all-or nothing transaction of Grid services, and introduce the Ecc metric to evaluate related service scheduling. The analysis of Ecc estimation is based on the so-called cc-prec commit pattern, which is an abstract of a category of common use cases of commit handling. Our analysis theoretically illustrates the high degree of computational complexity of scheduling optimization with respect to the cost labeling, timing and order of requests. Under certain typical conditions we prove that infinite possible schemes of scheduling can be reduced down to a finite set of candidates of scheduling. Especially based on the Ecc metric, the caution scheduling is thoroughly investigated, which as a basic policy could be employed in certain common scenarios, and under which the intuitive product-first or cost-first schemes are justified in several typical situations. (c) 2008 Elsevier Inc. All rights reserved.
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