A method and system are provided for reducing garbage collection overhead. The method includes representing, by a hardware processor, an application program by a Directed Acyclic Graph having a set of nodes. Each of the nodes represents a respective one of a plurality of computation tasks. The method further includes specifying, by the hardware processor from the set of nodes, any of the nodes which store a respective computation result for at least a threshold period of time as cache nodes. The method further includes allocating, by the hardware processor, the respective computation result of each of the cache nodes into a tenure area of a memory.