| 摘要 |
PURPOSE:To copy an address space at a high speed without reducing the applicable area of the address space by providing another address space for copy. CONSTITUTION:In a copy mode a dummy process generating part W produces an address space Z2 and a page table G2 and performs copying from an address space Z1 which is used for execution of information processings. If an invalid cell exists within a page of a file, only the valid cells are copied at a real memory copy control part M with the invalid cell left as it is. Therefore an area where only free cells exist. If no invalid cell exists within a page of the file and in an area where the copying should be carried out, only the pointers showing page positions of a real memory J1 and a paging auxiliary memory part J2 are copied to the table G2 within the space Z2. In this case, the data in a cell of the space Z1 is not copied to an area corresponding to the space Z2. |
