Using distributed information about lock conversion requests to efficiently manage lock state transitions
US6704767B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 2001 |
| Grant date | Mar 9, 2004 |
| Priority date | — |
| Expiry date | Sep 2, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99938
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A system for managing locks that give permission to access resources in a computer system is disclosed. The lock management system is distributed and provides deadlock protection. The lock management system is distributed in that information about which locks have been granted for a resource is stored at both a master node and at the nodes on which are located processes that desire to access to the resource. A master resource object located on the master node grants locks to shadow resource objects located on the nodes on which are located the processes that desire to access the resource. Each shadow resource object grants locks on the resource to the processes that are located on the same node as the shadow resource object. The shadow resource object includes a convert queue used to maintain a list of convert requests made by various processes. The lock request for the process is granted when the lock request is at the head of the convert queue. When granting the first lock request, other lock requests in the queue are granted if they are compatible with the locks granted by the shadow resource object.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.