US 6,687,794 B2 · Prefetching mechanism for data caches

Abstract

A data structure to aid in and a method, system, and computer program product for prefetching data from a data cache are provided. In one embodiment, the data structure includes a prediction history field, a next line address field, and a data field. The prediction history field provides information about the success of past data cache address predictions. The next line address field provides information about the predicted next data cache lines to be accessed. The data field provides data to be used by the processor. When a data line in the data cache is accessed by the processor, determines the value of a prediction history field and the value of a next line address field. If the prediction history field is true, then the next line address in the next line address field is prefetched. Based on whether the next line actually utilized by the processor matches the next line address in the next line address field, the contents of the prediction history field and the next line address filed are modified.

Claims20

Dependent claims

A data cache in a processor for storing data for access by an application program being executed within the processor, comprising:

a data structure stored in the data cache, the data structure including information used by the processor and including:
a plurality of data lines in the data cache, each of the data line comprising:
a prediction history field, wherein the prediction history field provides information about the success of past data cache address predictions;
a next line address field, wherein the next line address field provides information about the predicted next data cache lines to be accessed;
and
a data field, wherein the data field provides data for use by the processor.

3 more elements

Dependencies are inferred from the claim text.

Prefetching mechanism for data caches

Life of this patent

Prefetching mechanism for data caches

Life of this patent

Abstract

Claims20