16 | 16 | Resource Manager is required only if a computational cluster is used in the system. Its logic is also straightforward and directly depends on the policies of the cluster used. We tested our framework on the [http://www.rug.nl/cit/hpcv/faciliteiten/HPCCluster?lang=en Millipede HPC cluster] , which appears in the TOP500 supercomputers list. This cluster has a policy that any cluster job execution should not exceed the ten days limit to assure availability of cluster resources to all users. This means, that Resident Worker cannot run longer that ten days either. In our current implementation to keep a cluster as a part of our computational cloud, Resident Worker starts a new Resident Worker node in some time before it will be removed by the cluster administrator, e.g. two days before the end of a ten-days period. A request for starting a new Resident Worker is passed to the cluster scheduler and processed in some time depending on a cluster load. Hence, we assure that at least one Resident Worker is running on the cluster. |