Embodiments for leveraging directed acyclic graph (DAG) information to group tasks for execution, by at least one processor. An Input/Output (I/O) cost for each task in a set of tasks determined to be within a same input host set is determined, and tasks within the set of tasks are grouped into task groups according to an applied allocation time. The task groups are launched commensurate with a calculated delay time from each input host set so as to overlap I/O phases and central processing unit (CPU) phases to improve CPU efficiency. The launched task groups are executed by an executor according to the calculated delay time.