Passive serialization in a multitasking environment
US4809168A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 1986 |
| Grant date | Feb 28, 1989 |
| Priority date | — |
| Expiry date | Oct 17, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F9/466
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a multi-processing computer system, a method for serializing references to shared data objects, such as pages, tables, and the like, that permits the system processes to reference objects on a shared access basis without obtaining a shared lock. A point of execution of the control program is monitored that is common to all processes in the system, which occurs regularly in the execution of each process and across which no references to any data object can be maintained by any process, except references using locks. A system reference point is established, which occurs after each process in the system has passed the monitored point of execution at least once since the last such system reference point. Operations requiring exclusive access, such as modification or destruction of the data object, are performed by, first, obtaining a conventional exclusive lock, then preventing any subsequent references to the data object, waiting until two of the system reference points have occurred, and, finally, performing the operation. Significant reductions in overhead can be achieved through the application of the invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.