Method and apparatus for dynamically adjusting power/performance characteristics of a memory subsystem

• Main Authors: DOMEN; STANLEY J, IDATE; DILEEP R, THANGADURAI; GEORGE, GUNTHER; STEPHEN H
• Format: Patent
• Language: English
• Published: 12.01.1999
• Edition: 6
• Subjects: CALCULATING; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION ANDCOMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION ANDCOMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THIR OWNENERGY USE; COMPUTING; COUNTING; ELECTRIC DIGITAL DATA PROCESSING; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; INFORMATION STORAGE; PHYSICS; STATIC STORES; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

An apparatus and method for dynamically adjusting the power/performance characteristics of a memory subsystem. Since the memory subsystem access requirements are heavily dependent on the application being executed, static methods of enabling or disabling the individual memory system components (as are used in prior art) are less than optimal from a power consumption perspective. By dynamically tracking the behavior of the memory subsystem, the invention predicts the probability that the next event will have certain characteristics, such as whether it will result in a memory cycle that requires the attention of a cache memory, whether that memory cycle will result in a cache memory hit, and whether a DRAM page hit in main memory will occur if the requested data is not in one of the levels of cache memory. Based on these probabilities, the invention dynamically enables or disables components of the subsystem. By intelligently adjusting the state of these components, significant power savings are achieved without degradation in performance.