摘要: Virtualization technology was developed in the late 1960s to make more efficient use of hardware. Hardware expensive, and there not that much available. Processing largely outsourced few places did have computers. On a single IBM System/360, one could run parallel several environments maintained full isolation gave each its customers illusion owning time sharing implemented at coarse-grained level, key achievement technology. It also provided ability manage resources efficiently, as they would be assigned virtual machines such deadlines met certain quality service achieved.