1. A virtual machine deployment planning method comprising the steps of: receiving information about relationships of activation items in a plurality of virtual machines; said information also including activation item descriptive parameters; optimizing an activation order of said activation items in said virtual machines according to said relationships among said activation items by: determining an initial planning order of the virtual machines by: determining if a number of an activation item in a virtual machine which depends on activation of an activation item in another virtual machine is larger than a number of an activation item in said another virtual machine which also depends on activation of an activation item in said virtual machine, further determining if the activation of said virtual machine as a whole depends on the activation of said another virtual machine and if not, also determining if said activation of said another virtual machine as a whole depends on said activation of said virtual machine; constructing a whole dependence relationship tree according to determined dependence relations of activation of said virtual machines; and determining initial planning order according to an order from a virtual machine which is either most independent or dependent on any virtual machine by examining said relationship tree, wherein an order of activating said virtual machines which are equally dependent on is arbitrarily is selected; and with respect to each of said virtual machines, optimizing said activation order of the activation items inside the virtual machine according to said initial planning order of said virtual machines; and generating an activation logical file according to said optimized activation order and said activation item descriptive parameters.