A task execution method includes receiving an execution request for a first task; analyzing the first task and dividing the first task into sub-tasks, the sub-tasks including a first sub-task and a second sub-task; calculating respective deadline times of the sub-tasks; scheduling the sub-tasks for processing by resources, the resources using neural networks; sequentially executing the sub-tasks using the resources and the neural networks; checking whether respective runtimes of the sub-tasks exceed a corresponding deadline time; and executing the second sub-task, subsequent to executing the first sub-task, using a first pruned neural network generated from the neural networks when the checking indicates that the runtime of the first sub-task exceeds the deadline time of the first sub-task.