A modular meta-scheduling architecture for interfacing with pre-WS and WS Grid resource management services

The last version of the Globus Toolkit includes both pre-WS and WS GRAM services to submit, monitor, and control jobs on remote Grid resources. In the medium term and until a full transition is accomplished, both pre-WS and WS GRAM services will coexist in Grid infrastructures. In this paper, we describe the modular architecture of the GridWay meta-scheduler, which allows the simultaneous and coordinated use of pre-WS and WS GRAM services and, therefore, makes easy the transition to a Web Service implementation of the Globus components. Such functionality is demonstrated on a infrastructure that comprises resources from a research testbed, based on the Globus Toolkit 4.0, and the EGEE production infrastructure, based on the LCG middleware. The Web Service implementation of Globus components has been optimized for flexibility, stability and scalability. However, part of the Grid community is still reluctant to transition to the Web Service model due mainly to its supposed lower performance. We demonstrate that WS GRAM achieves a performance comparable to that of pre-WS GRAM.