US 7,627,719 B2 · Cache device and method for determining LRU identifier by pointer values

Abstract

The invention provides a cache device and method for performing a cache process on a cache memory having a high capacity in a high speed. The cache processing section performs a cache process composed of two-stage processes, a query process (P1) and a subsequent process (P2). In the query process (P1), the respective index tables and the identifier table are used to query whether the target identifier is present in the cache memory at a step (S101). If it is present, a data address of the target identifier in the cache memory is transmitted to the CPU. Otherwise, a data address of an identifier for a previously prepared ultimate LRU in the cache memory is transmitted to the CPU at a step (S102). In a subsequent process (P2), adjustment operations for the respective tables, regarding insertion of an identifier for a new data and deletion of the identifier for the ultimate LRU data, are performed at a step (S201).

Claims7

Dependent claims

A cache device, comprising:

a cache memory for storing data;
a module for performing a query on identifiers for data stored in a cache memory;
a module for outputting an address of a hit identifier if a query result is hit, and outputting an address of a previously prepared LRU identifier if it is not hit;
a module for determining an LRU identifier at a current timing, for a next time query;
and
a module for storing pointer values in an increment sequence of data write and read in correspondence with identifiers for data to be written and read, each time when the data are written and read;
and a module for determining the LRU identifier by the pointer values, and modifying all the pointer values when the maximum value of all the pointer values reaches a given value.

4 more elements

A cache method, comprising:

a process for performing a query on identifiers for data stored in a cache memory;
a process for outputting an address of a hit identifier if a query result is hit, and outputting an address of a previously prepared LRU identifier if it is not hit;
a process for determining an LRU identifier at a current timing, for a next time query;
and
storing pointer values in an increment sequence of data write and read in correspondence with identifiers for data to be written and read, each time when the data are written and read;
determining the LRU identifier by the pointer values, and modifying all the pointer values when the maximum value of all the pointer values reaches a given value.

3 more elements

Dependencies are inferred from the claim text.

Cache device and method for determining LRU identifier by pointer values

Life of this patent

Cache device and method for determining LRU identifier by pointer values

Life of this patent

Abstract

Claims7