Abstract: Provided are a virtual computing accelerator and program downloading method for server-based virtual computing. The virtual computing accelerator divides a program allocated to a virtual memory into groups, such as pages or segments, and downloads the groups of program data in sequence. Here, the groups of program data are downloaded after download sequence is estimated on the basis of statistical data accumulated in a hash table, or only a part that must be first downloaded is downloaded in advance. Thus, a program-execution wait time of a client can be reduced. In addition, only a part of a possibly required program is transferred in advance, and the client can execute the application program using only a small amount of virtual memory.