Patent · US Expired

Hardware mechanism for optimizing instruction and data prefetching by forming augmented prefetch instructions

US5761468A · kind A · utility

54Cited by
15References
30Claims
0Family size

Inventor

Key dates

Filing dateMay 15, 1996
Grant dateJun 2, 1998
Priority date
Expiry dateMay 15, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2212/6028
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Disclosed is a prefetch execution unit, prefetch instruction buffer and a prefetch victim buffer which operate to optimize prefetching by recording a particular cache miss' history. To record cache misses, victimized (overwritten) lines and/or a prefetch tag are stored in a prefetch victim buffer. When the processor experiences a cache miss, it accesses the prefetch victim buffer to retrieve information relating to the prefetch victim. The prefetch execution unit then modifies the values of the additional field or fields and then stores the modified augmented prefetch instruction in the prefetch instruction buffer. The next time a prefetch instruction for the victimized lines is executed by the processor, the new values of the modified augmented prefetch instruction will dictate where the prefetch information is stored or what size increment it has. By continuous modification of the augmented prefetch instructions, eventually thrashing may be eliminated.

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