Monere: Monitoring of Service Compositions for Failure Diagnosis

Service-oriented computing has enabled developers to build large, cross-domain service compositions in a more routine manner. These systems inhabit complex, multi-tier operating environments that pose many challenges to their reliable operation. Unanticipated failures at runtime can be time-consuming to diagnose and may propagate across administrative boundaries. It has been argued that measuring readily available data about system operation can significantly increase the failure management capabilities of such systems. We have built an online monitoring system for cross-domain Web service compositions called Monere, which we use in a controlled experiment involving human operators in order to determine the effects of such an approach on diagnosis times for system-level failures. This paper gives an overview of how Monere is able to instrument relevant components across all layers of a service composition and to exploit the structure of BPEL workflows to obtain structural cross-domain dependency graphs. Our experiments reveal a reduction in diagnosis time of more than 20%. However, further analysis reveals this benefit to be dependent on certain conditions, which leads to insights about promising directions for effective support of failure diagnosis in large Web service compositions.