Abstract: A technology is described for determining a launch workflow for launching multiple computing instances on a physical host in a computing service environment using a predicted launch time. An example method may include receiving a launch plan to launch a plurality of computing instances on a physical host within a computing service environment. A first launch workflow and a second launch workflow may then be determined for the launch plan where the first launch workflow and the second launch workflow may specify different sequences of operations performed to launch the computing instance on the physical host. Predicted launch times for the first launch workflow and the second launch workflow may be obtained and the predicted launch times may be compared to determine a launch workflow used in executing the launch plan.