Memory access control system

Abstract

Abstract PURPOSE: To improve system performance by allowing a processor, not in charge, to set the lock bit of a corresponding block in a directory during the exclusive access period of a main memory and by locking the main memory, block by block in a cash memory. CONSTITUTION: Processor CPU 1 holds the address and effectiveness display bit of information read out to cash memory unit CM 1 corresponding to blocks of memory CM 1 , and sldo has the lock bit indicating that the blocks have been locked in directory DR 1 . While the other processor CPU 2 is inhibited from attaining access to main memory MM during the exclusive access execution period of the main memory, the lock bits of a corresponding block in directory DR 1 is set and the locking of the main memory to inhibit CPU 2 from attaining access to main memory MM is done on the unit of the block of memory CM 1 . Consequently, the performance of the system can be improved. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Tadao Kondo

Bibliographic Details