Inventors:
Wayne R. Buzby - Phoenix AZ
Charles P. Ryan - Phoenix AZ
Assignee:
Bull HN Information Systems Inc. - Billerica MA
International Classification:
G06F 1200
US Classification:
711130, 711118, 711119, 711120, 711121, 711122, 711147
Abstract:
In a multiprocessor data processing system including: a memory, first and second shared caches, a system bus coupling the memory and the shared caches, first, second, third and fourth processors having, respectively, first, second, third and fourth private caches with the first and second private caches being coupled to the first shared cache, and the third and fourth private caches being coupled to the second shared cache, gateword hogging is prevented by providing a gate control flag in each processor. Priority is established for a processor to next acquire ownership of the gate control word by: broadcasting a âset gate control flagâ command to all processors such that setting the gate control flags establishes delays during which ownership of the gate control word will not be requested by another processor for predetermined periods established in each processor. Optionally, the processor so acquiring ownership broadcasts a âreset gate control flagâ command to all processors when it has acquired ownership of the gate control word.