Caching of machine images

Technology is described for reducing computing instance launch times. A computing instance that is expected to be launched in a computing service environment during a defined time period may be identified. A machine image associated with the computing instance may be determined to be cached in the computing service environment using a launch time prediction model to reduce a launch time for launching the computing instance as compared to not caching the machine image. At least one physical host in the computing service environment that is available to cache the machine image may be selected to lower the launch time of the computing instance as predicted by the launch time prediction model. The machine image may be stored in the physical host in order to minimize the launch time for launching the computing instance in the computing service environment, using the processor.