In one embodiment, a method includes accessing a computational graph representing computations to be executed on a computing system comprising a plurality of Execution Units (EUs), identifying a set of candidate mapped-graphs for the computational graph, where each node in a candidate mapped-graph is mapped to an EU capable of calculating the node, ensuring that each edge from a first node to a second node in each candidate mapped-graph satisfies memory constraints, determining an expected cost for executing each candidate mapped-graph using mapped-EUs in the candidate mapped-graph for calculating respective nodes, and selecting a candidate mapped-graph with a least expected cost from the set of candidate mapped-graphs.