System and method for adaptively managing pages in a memory
AssigneeInternational Business Machines Corporation
InventorsNimrod Megiddo, Dharmendra Shantilal Modha
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Abstract
An adaptive replacement cache policy dynamically maintains two lists of pages, a recency list and a frequency list, in addition to a cache directory. The policy keeps these two lists to roughly the same size, the cache size c. Together, the two lists remember twice the number of pages that would fit in the cache. At any time, the policy selects a variable number of the most recent pages to exclude from the two lists. The policy adaptively decides in response to an evolving workload how many top pages from each list to maintain in the cache at any given time. It achieves such online, on-the-fly adaptation by using a learning rule that allows the policy to track a workload quickly and effectively.
Claims20
A method for adaptively managing pages in a memory, comprising:
- defining a cache memory;
- defining a cache directory;
- organizing the cache directory into four disjoint lists of pages:
- list T1, list T2, list B1, and list B2;
- and
- wherein the cache memory contains pages that are members of any of the list T1 or the list T2.
An apparatus for adaptively managing pages in a memory, comprising:
- a cache memory;
- a cache directory that is organized into four disjoint lists of pages:
- list T1, list T2, list B1, and list B2;
- and
- wherein the cache memory contains pages that are members of any of the list T1 or the list T2.
A computer program product having a plurality of executable instruction codes that are stored on a computer-readable medium, for adaptively managing pages in a cache memory, comprising:
- a first set of instruction codes for organizing a cache directory into four disjoint lists of pages:
- list T1, list T2, list B1, and list B2;
- and
- wherein the cache memory contains pages mat are members of any of the list T1 or the list T2.
Dependencies are inferred from the claim text.