Patent ID: 8108629
Filing Date: 2012-01-31
Classification: G06F,G11C,Y02D

Abstract:
1. A memory management method in a computer system having a processor and a memory for storing information referred to by the processor, the memory including a plurality of memory banks, each of the memory banks having a plurality of physical pages, each of the memory banks having a respective power supply that is independently controlled, the memory management method comprising: creating a use frequency list indicating an order of respective use frequencies of the physical pages of the memory banks of the memory; registering at least one of a maximum value, a minimum value, and an average value of the respective use frequencies of the physical pages for each memory bank in a memory bank management table; selecting one of the memory banks of the plurality of memory banks as a migration destination of a first physical page of the physical pages based on the at least one of the maximum values, the minimum values, and the average values of the respective use frequencies registered for the memory banks in the memory bank management table; determining whether there is an unused physical page in the memory bank selected as the migration destination; upon determining that there is an unused physical page in the memory bank selected as the migration destination, moving contents of the first physical page to the unused physical page in the memory bank selected as the migration destination and updating the use frequency list and the memory bank management table to reflect moving of the contents of the first physical page to the unused physical page; upon determining that there is not an unused physical page in the memory bank selected as the migration destination, selecting a second physical page from the memory bank selected as the migration destination, interchanging the contents of the first physical page with contents of the second physical page, and updating the use frequency list and the memory bank management table to reflect interchanging of the contents of the first physical page with the contents of the second physical page; determining to control the respective power supply of one of the memory banks of the plurality of memory banks selected based on the at least one of the maximum values, the minimum values, and the average values of the respective use frequencies registered for the memory banks in the memory bank management table upon updating the memory bank management table; and setting the respective power supply for the memory bank selected for having the respective power supply of which controlled in a low power consumption mode.