It is our contention that distributed applications might prosper better when the resource information from across the entire system is available quickly and locally for decision support rather than having to have each participating node contact a server (e.g. farm-monitoring unit in case of MonaLisa) every time a new scheduling or reconfiguration decision has to be made.  GEMS provides such a service with fault tolerance, which intimates all the nodes in the system of a failure within milliseconds depending upon the configuration.  We believe that GEMS is highly suited as a lower-level service for load-balancing and scheduling middleware as well as for application-level decisions.

MonaLisa (MONitoring Agents using a Large Integrated Services Architecture) is a powerful and widely recognized monitoring service especially in the grid community.  MonaLisa seems to better suit inter-domain operations (that require crossing administration boundaries) versus intra-domain operations.    Grid or inter-site operations, at least as they are deployed now, require a single gatekeeper or point of contact at every site.  The gatekeeper can thus provide the services of the farm-monitoring unit, such as data caching, web services, event notification, etc.,  With its highly efficient graphical interface and the services provided with JINI, MonaLisa can be a very efficient coordinating tool (of other intra-site monitoring services).

Thus, the primary idea here is to build a service that takes advantage of the features of both GEMS and MonaLisa, and thus serves distributed applications in a more reliable, robust and efficient manner.  The service has GEMS as the distributed intra-site monitoring service at the participating sites coordinated by MonaLisa thus removing the potential hot spot at the farm-monitoring unit and reducing the chances of the unit being a single point of failure within a cluster.  The farm-monitoring unit running on the gatekeeper can acquire the details of the system from any node in the system.  In future, if the fixed gatekeeper concept is eliminated, the services provided by the farm-monitoring unit could also be distributed.  With MonaLisa coordinating many such GEMS agents, a full-fledged, highly flexible, dynamic, adaptive, and user-friendly monitoring service that serves applications of any scale directly or via load-balancing and scheduling middleware is a bright prospect.

 

 

LIVE DEMO:  First version of MonALISA/GEMS can be viewed live here by following the instructions below: