A system, method, and computer program product for semi-synchronously copying data from a first portion of memory to a second portion of memory are disclosed. The method comprises receiving, in a processor, a call for a semi-synchronous memory copy operation. The semi-synchronous memory copy operation preserves temporal persistence of validity for a virtual source address corresponding to a source location in a memory and a virtual target address corresponding to a target location in the memory by setting a flag bit. The call includes at least the virtual source address, the virtual target address, and an indicator identifying a number of bytes to be copied. The memory copy operation is placed in a queue for execution by a memory controller. The queue is coupled to the memory controller. At least one subsequent instruction is continued to be executed as the subsequent instruction becomes available from an instruction pipeline.