Patent ID: 9557933
Date: 2017-01-31
CPC Classifications: G06F

Claim:
1. A method of migrating data for a logical device, comprising: subdividing the logical device into subsections for use with migrating the data, wherein each of the subsections corresponds to a particular address range of the logical device that is mapped to a physical device containing corresponding data; copying data for a particular subsection from a first physical device to a second, different, physical device, wherein the data of the particular subsection that is copied to the second physical device is scheduled for temporary storage on the second physical device as a working set copy of the data of the particular subsection for input/output (I/O) processing for a time period corresponding to expected higher activity level based on historical access information; during the time period, servicing received I/O requests for the data of the particular subsection using the working set copy of the data of the particular subsection present on the second physical device; after the time period, updating the data for the particular subsection present on the first physical device using the working set copy of the data for the particular subsection present on the second physical device as modified by any received I/O requests; and releasing memory used to store the working set copy of the data of the particular subsection on the second physical device after updating the data for the particular subsection present on the first physical device.