Exploiting Dynamic Deployment in a Distributed Query Processor for the Grid

摘要

Grid computing has enabled users to perform computationally expensive applications on distributed resources acquired dynamically. It has also allowed users to combine data and analysis components into new applications from sites all over the world. Often such distributed data is structured, and an established way of structuring computations is found in distributed query processing. The established Grid tools like OGSA-DAI and OGSA-DQP provide respectively a common interface to different underlying databases and a way of expressing a global schema which unites the distributed resources and supports evaluation of declarative queries in distributed fashion. While Grid computing offers these significant benefits to a user, it also incurs the difficulties that arise through distribution, especially at wide area scale, on non-dedicated resources. Computation and communication costs can both be significant and vary significantly. In such contexts, a range of techniques for dynamic adaptation of distributed queries need to be employed in order to ensure reasonably efficient execution. DynaSOAr is an infrastructure for dynamically deploying web services over a set of networked resources with virtualization features thereby creating support for ad-hoc Virtual Organisations.