Data stream prefetching in a microprocessor

US7350029B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Eric Jason Fluhr · Round Rock, US
• Bradly G. Frey · Austin, US
• John B. Griswell, Jr. · Austin, US
• Hung Q. Le · Austin, US
• Cathy May · Ossining, US
• Francis Patrick O'Connell · Austin, US
• Edward John Silha · Austin, US
• Albert Thomas Williams · Austin, US

Key dates

• Filing date: Feb 10, 2005
• Grant date: Mar 25, 2008
• Expiry date: Nov 17, 2025

Classification

• Technology area (CPC G): Physics
• CPC primary: G06F2212/6028
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

A method of prefetching data in a microprocessor includes identifying a data stream associated with a process and determining a depth associated with the data stream based upon prefetch factors including the number of currently concurrent data streams and data consumption rates associated with the concurrent data streams. Data prefetch requests are allocated with the data stream to reflect the determined depth of the data stream. Allocating data prefetch requests may include allocating prefetch requests for a number of cache lines away from the cache line currently being referenced, wherein the number of cache lines is equal to the determined depth. The method may include, responsive to determining the depth associated with a data stream, configuring prefetch hardware to reflect the determined depth for the identified data stream. Prefetch control bits in an instruction executed by the processor control the prefetch hardware configuration.