Symmetric/asymmetric shared processing operation in a tightly coupled

Abstract

In a data base processing system using a multiprocessor system, the data base processing system includes: a storage unit provided in the shared memory for storing data base management information representing either an object of a shared processing operation or an object of a local processing operation for every resource; an access management unit provided in each of the processor modules for performing an access control for an access request to the data base under either the shared processing operation or the local processing operation in accordance with the data base management information, the shared processing operation being symmetrically performed, and the local processing operation being asymmetrically performed in each processor module; and a control unit provided in the processor module for controlling the shared/local conversion in such a way that: an access state of the resource is managed for every resource; when a frequency of the access is unevenly distributed to a particular processor module, the resource of that processor module is determined as the object of the local processing operation at that particular processor module; and when the frequency of the access is not unevenly distributed to a particular processor module, the resource of a particular processor module is determined as the object of the shared processing operation. The data base processing system further includes a deadlock detection system.