Efficient lock state transitions in a distributed system
US6618744B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 1, 2001 |
| Grant date | Sep 9, 2003 |
| Priority date | — |
| Expiry date | Jul 12, 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 are 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. A shadow resource object may retain a lock on a resource even when no process on the same node requires the shadow resource to retain the lock. Whether a shadow resource retains a lock under these circumstances depends on conditions in the system, including whether most processes accessing the resource reside on the same node as the shadow resource.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.