| 摘要 |
PURPOSE:To reduce the deterioration of performance of a lock control system by preventing previously the transmission of a reference request from a processor to the region of a main memory which is locked by another processor. CONSTITUTION:A task selection circuit 6 transmits a reference address to a main memory 3 via a signal line 10 for reference of a header of the start queue or a control block. In this case, the reference address on the line 10 with the address of a control block or a header on a signal line 13 through a comparator 5 if the lock signal on a signal line 9 is set at (1). The coincidence or the discordance of the comparator 5 is informed to the circuit 6. When the coincidence is obtained, it means that an arithmetic processor 1 is referring or will soon refer the header or the control block to which the circuit 6 is going to refer. In such a case, the circuit 6 does not set the reference request on a signal line 11 at (1) and starts selection of another I/O task. If the lock signal on the line 9 is set at (0), the comparator 5 delivers a discordance signal to a signal line 15. Therefore the circuit 6 sets the reference request on the line 11 at (1) and starts the reference to the header or the control block on the memory 3. |
