| 摘要 |
PURPOSE:To reduce the overheads as less as possible which are produced with an exclusive access given to a queue by securing such a constitution where a channel processor which decides incapability of its service against the queue turns on its own control flag and stops its subsequent services. CONSTITUTION:A channel processor 5 turns on a control bit 22 corresponding to the processor 5 itself out of both control bits 22 and 23 contained in a control table 17 when the first exclusive occupation of the table 17 is released. When the processor 5 tries to occupy the table 17 again, the processor 5 recognizes that the bit 22 is kept ON and therefore avoids the exclusive occupation of the table 17. As a result, the service is never disturbed by a channel processor 6 to the 2nd path group 2. Then the processor 6 starts its service to the group 2 and therefore clears both bits 22 and 23 when a subchannel 20 is turned into a dequeue state from a queue state. |
