[[PageOutline]] = !QosCosGrid = == Introduction == !QosCosGrid could be viewed as a ''quasi-opportunistic supercomputer'' whose computational performance exceeds the power offered by a single supercomputing or data center. !QosCosGrid is designed as a multi-layered architecture that is capable of dealing with computationally intensive large-scale, complex and parallel simulations that are usually too complex to run within a single computer cluster or machine. The !QosCosGrid middleware enables computing resources (at the level of processor cores) from different administrative domains to be combined into a single powerful computing resource via Internet. Clearly, bandwidth and latency characteristics of the Internet may have an affect on overall application performance of !QosCosGrid-enabled applications. However, the ability to connect and efficiently control advanced applications executed in parallel over the Internet is a feature that is highly appreciated by !QosCosGrid users. === QCG Middleware === In a nutshell, the !QosCosGrid middleware consists of two logical levels: grid domain and administrative domain. Grid-level services control, schedule and generally supervise the execution of end-users applications, which are spread between independent administrative domains. The administrative domain represents a single resource provider (e.g. HPC or datacenter) participating in a certain Grid or Cloud environment by sharing its computational resources, e.g. computing clusters, with both local and external end-users. The logical separation of administrative domains corresponds with the fact that they are possessed by different institutions or resource owners. Each institution contributes its resources for the beneļ¬t of the entire Grid or Cloud, while controlling its own administrative domain and own resource allocation/sharing policies. The key component of every administrative domain in !QosCosGrid is the [[QCG_BES|QCG BES/AR service]], which gives the remote access to queuing systems resources. QCG BES/AR supports advance reservations, parallel execution environments - OpenMPI, !ProActive and MUSCLE with coordinators responsible for synchronization of cross-cluster executions (see [[QCG_libraries_and_cross-cluster_communication|Cross-cluster communication]]) and [[QCG_DataMovement|QCG Data Movement services]] for managing input and output data. The another relevant service at the administrative domain is in charge of notification mechanism and it is called [[QCG_Notification|QCG Notification]]. These services are tightly integrated and connected to the Grid-level services. The critical service on this level is [[QCG_Broker|QCG Broker]], that is a meta-scheduling framework controlling executions of applicaitons on the top of queuing systems via Smoa Computing services. !QosCosGrid architecture is depicted in the figure presented below. [[Image(QCG-Architecture-v4.png, center, width=700px)]] === End-user Information === === Developer & Admin Information === === Community === == News == == Download & Install == == Interoperability & standards supported == == Publications & Talks