| 摘要 |
PURPOSE:To realize the use of magnetic disk devices in a number exceeding the limitation of both the software and the hardware, by using the virtual magnetic disk devices which are obtained by virtually dividing a real magnetic disk device into an optional number of devices. CONSTITUTION:The virtual magnetic disk devices are obtained by virtually dividing a real magnetic disk device 3a into an optional number of devices, and the information of this virtual magnetic disk device is stored into a physical volume directory table provided within the device 3a. The information in all of the said directory tables is stored into a control table 4. Then the supervisor is called out to designate the identifier of the virtual magnetic disk device, and the use start request is given to retrieve the table 4. The information of the virtual magnetic disk device corresponding to the identifier is written into an idle record in a volume mount table 1a and a PUB table 2a respectively. The table 1a is retrieved by using the identifier as the key to obtain the pointer information to be given to the table 2a. This pointer information is designated to request an input/output to the supervisor. |
