Patent ID: 6098153
Filing Date: 2000-08-01
Classification: G06F

Abstract:
A method for determining an appropriate amount of data to stage in cache memory in a data processing comprising the steps of:a) determining a history of data accessing and storage on a disk, the disk including a plurality of regions, each of the plurality of regions having at least one sub-region, wherein each of the plurality of regions is associated with a plurality of counters, each of the plurality of counters corresponding to one the plurality of staging modes, the step of determining a history further comprising the steps of:a1) determining which one of the plurality of staging modes should have been used based upon a data reference type; anda2) incrementing a counter, the counter being one of the plurality of counters associated with the region and corresponding to the one of the plurality of staging methods that should have been used;b) maintaining within a cache directory a data structure for each of the plurality of sub regions, said data structure comprising:b1) a data segment identifier of an originally referenced data segment; andb2) a plurality of indicators; wherein, a first indicators of the plurality of indicators is set when a current reference is to a data segment positioned in the sub-region after the originally referenced data segment, and a second indicator is set when a current reference is to a data segment positioned in the sub-region before the originally referenced data segment, for establishing the data reference type; andc) predicting an optimal staging mode from a plurality of staging modes based upon the history.