Patent ID: 8856397
Filing Date: 2014-10-07
Classification: G06F

Abstract:
1. A method for determining one or more candidates for data movement comprising: determining, for each of one or more extents of each of one or more logical devices, extent activity level information and an activity map, said extent activity level information including one or more metrics indicating an activity level for said each extent, each of said one or more extents of each of said one or more logical devices including a plurality of sub extents, said activity map for said each extent including an entry for each sub extent included in said each extent, said entry indicating an activity level for said each sub extent; and selecting a first sub extent of a first extent of a first of the one or more logical devices as a candidate for data movement between different storage tiers, wherein said selecting is performed using information including said extent activity level information and said activity map for said first extent, wherein said first sub extent is selected as a candidate for promotion, from a first storage tier of physical devices to a second storage tier of physical devices providing higher performance than the first storage tier, based on a corresponding entry for the first sub extent in the activity map for the first extent whereby the corresponding entry indicates an activity level for the first sub extent.