1. A method for closing application programs of an application system, wherein the application programs are deployed on a series of virtual machines, and each virtual machine runs one or more application programs, the method comprising: when the application system is to be closed, a cloud service platform determining virtual machines running application programs of the application system according to configuration information of the application system; wherein the configuration information of the application system comprises: close orders of the application programs in the application system, and virtual machines corresponding to each application program; and the cloud service platform sending indication messages for closing the application programs of the application system to the virtual machines running application programs of the application system, wherein, the indication messages are used for indicating the virtual machines to close the application programs of the application system in a sequence based on close orders of the application programs in the configuration information; wherein the cloud service platform sending the indication messages to a control engine in each virtual machine running application programs of the application system, and the control engine is responsible for controlling sequential closing of the application programs run in the virtual machine.