1. A method comprising: generating a first set of configurations for a currently executing MapReduce job, wherein said set of configurations comprises job-level configurations and task-level configurations; dynamically modifying: (i) a distinct set of task-level configurations of a mapper component associated with at least one ongoing map task of the MapReduce job, based on the generated first set of configurations, wherein said task-level configurations of the mapper component comprise a size of a map task input, resource allocation for a mapper component, central processing unit, memory, a size of a sorting area, and a number of threads when writing a map output to a local disk, and (ii) a distinct set of task-level configurations of a reducer component associated with at least one ongoing reduce task of the MapReduce job, based on the generated first set of configurations, wherein said task-level configurations of the reducer component comprise a number of threads when copying a map output to a reducer component, a size of a reduce task input, resource allocation of a reduce task, central processing unit, memory, and a size of a sorting area; and deploying said modified configurations to the mapper component and the reducer component associated with the MapReduce job in accordance with one of multiple temporal deployment schedules, wherein the temporal deployment schedule is based on the contents of the modified configurations; wherein said generating, said modifying, and said deploying are carried out by one or more computing devices.