A method for modeling a hydrocarbon reservoir. A representation of a simulation model is generated in a non-transitory, computer readable medium. The simulation model is used to generate computational tasks. The tasks are allocated among a plurality of computational nodes. Each processing node of the plurality of computational nodes includes core processors and a shared memory accessible by the core processors. The reservoir simulation is executed on the plurality of computational nodes. During the reservoir simulation, if a first processing node in the plurality of computational nodes finishes executing its allocated tasks, a migration request is sent from the first processing node to another processing node in the plurality of computational nodes. The migration request is configured to request migration of a movable task from the other processing node to the first processing node. The movable task is migrated from the other processing node to the first processing node.