Patent · US Expired

Demand-based processor clock frequency switching

US6438697B2 · kind B2 · utility

16Cited by
20References
26Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 27, 2001
Grant dateAug 20, 2002
Priority date
Expiry dateMar 27, 2021

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02D10/00
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A battery powered computer system determines when the system is not in use by monitoring various events associated with the operation of the system. The system preferably monitors the number of cache read misses and write operations, i.e., the cache hit rate, and reduces the system clock frequency when the cache hit rate rises above a certain level. When the cache hit rate is above a certain level, then it can be assumed that the processor is executing a tight loop, such as when the processor is waiting for a key to be pressed and then the frequency can be reduced without affecting system performance. Alternatively, the apparatus monitors the occurrence of memory page misses, I/O write cycles or other events to determine the level of activity of the computer system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.