Implementation and Performance Analysis of XMatch: a Language for Quality-based Selection of Grid Services

Grid systems focus on the sharing and coordination of a large number of geographically- dispersed resources among different communities of users. Such systems require the capability of associating users requests to the actual resources. This capability should consider a high number of similar resources and different perceptions of users satisfaction concerning the selected resources. In order to face this problem, in our previous work we have proposed XMatch, a query language enabling the expression of the user request in terms of the expected satisfaction over XML-based representations of available resources. In this paper, we present an XMatch implementation consisting in rewriting XMatch queries in terms of XQuery expressions. We also propose a performance analysis based on real-world use cases. This implementation and evaluation of XMatch shows the suitability of the language for the identified use cases and the feasibility of its application.