1. A non-transitory machine readable storage medium comprising instructions embodied thereon, the instructions upon execution by a processor cause a system to: receive a request to launch a computing instance in a computing service environment, the request including placement constraints for placement of the computing instance during launch; provide instance features associated with the computing instance and physical host features associated with a group of physical hosts in the computing service environment to a machine learning model; determine estimated launch times for launching the computing instance on individual physical hosts in the computing service environment using the machine learning model, wherein the machine learning model uses historical launch time information to determine the estimated launch times in view of the instance features and the physical host features; and select a physical host from the group of physical hosts to provide placement of the computing instance according to a lower estimated launch time as compared to other physical hosts in the group of physical hosts and the placement constraints included in the request to launch the computing instance, wherein the physical host is selected for placement of the computing instance using a weighting value assigned to the estimated launch times for the computing instance.