摘要 |
<p>A Record Lock Processor provides a common facility for control of the locking and unlocking of mass storage objects (for example, records, files, pages or any other logical entity) that is shared by a number of loosely-coupled data processors. The terms "record" or "records" wherever they are used in this document are intended to refer to all such objetcs, including records, files, pages or any other logical grouping or entity into which the mass storage may be portioned. Each of the data processors has access to all of the shared mass storage. Three Lock Modules all receive the same requests and majority voting techniques are used to determine the result. A fourth lock module is included as a Hot Spare Module. A Maintenance Module receives the same requests as the voting Lock Modules and, therefore, it is able to interpret results on-line based on user requests. Programmable Channel Interfaces provide the operational interface to the host processors. The Lock Modules are also programmable, and they hold Lock and Queued Lock Requests and execute locking and unlocking algorithms in response thereto.</p> |