System and method for accessing a shared computer resource using a lock featuring different spin speeds corresponding to multiple states
US6578033B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 2000 |
| Grant date | Jun 10, 2003 |
| Priority date | — |
| Expiry date | Jan 24, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99938
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A probabilistic queue lock divides requesters for a lock into at least three sets. In one embodiment, the requesters are divided into the owner of the lock, the first waiting contender, and the other waiting contenders. The first waiting contender is made probabilistically more likely to obtain the lock by having it spin faster than the other waiting contenders. Because the other waiting contenders spin more slowly, the first waiting contender is more likely to be able to observe the free lock and acquire it before the other waiting contenders notice that it is free. The first of the other waiting contenders that determines that the previous first waiting contender has acquired the lock is promoted to be the new first waiting contender and begins spinning fast. Because only the first waiting contender is spinning fast on the lock, it is probable that only the first waiting contender will attempt to acquire the lock when it becomes available.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.