Considering a frequency of access to groups of tracks to select groups of tracks to destage
AssigneeInternational Business Machines Corporation
InventorsKevin J. Ash, Lokesh M. Gupta
Life of this patent
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Abstract
Provided are a computer program product, system, and method for considering a frequency of access to groups of tracks to select groups of tracks to destage. A first scanning of groups of tracks in the cache is performed to destage each of the groups of tracks having a group frequency satisfying a first frequency requirement. The group frequency indicates a frequency with which the tracks in the group are modified. A second scanning of groups of tracks in the cache is performed to destage each of the groups of tracks having the group frequency satisfying a second frequency requirement.
Claims17
A computer program product for selecting tracks to destage from a cache to a storage, the computer program product comprising a computer readable storage medium having computer readable program code embodied therein that when executed performs operations, the operations comprising:
- determining a mean frequency from a number of times tracks in groups of tracks in the cache were modified and a total number of the tracks in the groups of tracks in the cache that were modified;
- performing a first scanning of the groups of tracks in the cache to determine each of the groups of tracks having a first group frequency satisfying a first frequency requirement;
- destaging each of the groups of tracks determined to have the first group frequency satisfying the first frequency requirement;
- performing a second scanning of groups of tracks in the cache to determine each of the groups of tracks having a second group frequency satisfying a second frequency requirement, wherein the first and second frequency requirements are based on the mean frequency;
- and
- destaging each of the groups of track determined to have the second group frequency satisfying the second frequency requirement.
A system in communication with a storage, comprising:
- a processor;
- a cache;
- and
- a computer readable storage medium having computer program code that when executed by the processor perform operations, the operations comprising:
- determining a mean frequency from a number of times tracks in groups of tracks in the cache were modified and a total number of the tracks in the groups of tracks in the cache that were modified;
- performing a first scanning of the groups of tracks in the cache to determine each of the groups of tracks having a first group frequency satisfying a first frequency requirement;
- destaging each of the groups of tracks determined to have the first group frequency satisfying the first frequency requirement;
- performing a second scanning of groups of tracks in the cache to determine each of the groups of tracks having a second group frequency satisfying a second frequency requirement, wherein the first and second frequency requirements are based on the mean frequency;
- and
- destaging each of the groups of track determined to have the second group frequency satisfying the second frequency requirement.
A method computer program product for selecting tracks to destage from a cache to a storage, comprising:
- determining a mean frequency from a number of times tracks in groups of tracks in the cache were modified and a total number of the tracks in the groups of tracks in the cache that were modified;
- performing a first scanning of groups of tracks in the cache to determine each of the groups of tracks having a first group frequency satisfying a first frequency requirement;
- destaging each of the groups of tracks determined to have the first group frequency satisfying the first frequency requirement;
- performing a second scanning of groups of tracks in the cache to determine each of the groups of tracks having a second group frequency satisfying a second frequency requirement, wherein the first and second frequency requirements are based on the mean frequency;
- and
- destaging each of the groups of track determined to have the second group frequency satisfying the second frequency requirement.
Dependencies are inferred from the claim text.