The output rate variation problem stands as one of the important research directions in the area of multi-level just-in-time production system. In this short survey, we present the mathematical models of the problem followed by consideration of its NP-hardness. We further carry out the brief review of heuristic approaches that are devised to solve the problem. The dynamic programming approach and pegging assumption are also briefly discussed. The pegging assumption reduces the multilevel problem into weighted single-level problem. A couple of the open problems regarding ORVP are listed at the end.