Load Balancing

Abstract

Building a house comprises a large number of individual tasks such as digging a hole, laying the foundations, putting up walls, installing windows, wiring, and pipes, etc. Looking more closely, tasks consist of subtasks. For example, to put up a wall, you have to lay a large number of bricks. If you want to build fast, many workers have to cooperate. You have to plan which tasks can be done in parallel, what their dependencies are, and what resources (qualified workers, raw material, tools, space, . . . ) are needed. It is often difficult to estimate in advance how long a certain task is going to take. For example, raw materials may be delayed, a worker may fall ill, or a subtask may never have been done before. Hence, plans have to be revised as new information becomes available.