1. A method, comprising: determining, by a cluster management engine, available space in a virtual cluster of a plurality of communicatively coupled nodes included in a computing environment, each node including a cluster agent in communication with the cluster management engine, the virtual cluster associated with a group of users that submit similar jobs, and comprising a logical grouping of nodes configured to process related jobs; prior to job execution, determining an optimum job that is compatible with the available space in the virtual cluster of nodes; and following the determining, executing the optimum job in the available space in the virtual cluster of nodes; wherein determining the optimum job that is compatible with the available space in the virtual cluster of nodes further comprises: determining a number of available nodes in the virtual cluster; selecting a first job from a job queue; dynamically determining an optimum shape of the first job; determining whether the number of available nodes is enough to execute the first job, based on the optimum shape thereof; and dynamically allocating one or more of the available nodes for the first job, in the event that the determined number of available nodes is enough to execute the first job; wherein the optimum shape comprises one or more of: a best fit cube in which the one or more available nodes are allocated in a cubic volume so as to allow cooperating tasks to exchange data with any other tasks by minimizing the distance between any two nodes; and a best fit sphere in which the one or more available nodes are allocated in a spherical volume such that a first task is placed in a center node of the sphere with remaining tasks placed on nodes surrounding the center node so as to minimize the distance between the first task and the remaining tasks, wherein the remaining tasks communicate with the first task, but not with each other.