Patent ID: 8769225
Filing Date: 2014-07-01
Classification: G06F

Abstract:
1. A method of data migration between first and second storage mediums of an available plurality of storage mediums in a computing storage environment by a processor device, comprising: migrating the data from the first to the second storage medium, and allocating the data to the second storage medium while retaining an allocation of the data in the first storage medium; marking a mirroring indicator of the data on the first storage medium as mirroring the allocation of the data in the second storage medium, after the data on the first storage medium has been migrated to the second storage medium; using a bitmap to track whether space on the first storage medium has already been allocated or reserved; and pursuant to migrating data from the first to the second storage medium: a determination is made as to whether the data exists in both the first storage medium and the second storage medium thereby being mirrored, if the data is mirrored and the mirror is to be deleted, the data is pointed to the allocation of the data in the first storage medium to alleviate data movement from the second storage medium to the first storage medium, if a determination is made that only mirrored space remains in the first storage medium, mirrored data segments in the first storage medium are searched to determine whether an allocation of one or more of the mirrored data segments in the first storage medium is needed for other data, wherein to determine whether the allocation is needed for other data is based on a read/write ratio of the one or more mirrored data segments, the one or more mirrored data segments are allocated to a new purpose, and the allocation of the one or more mirrored data segments in the first storage medium is freed by clearing a mirroring indicator associated with the freed allocation of the one or more mirrored data segments, and if the data is mirrored and one of an allocation of the data in the second storage medium and the allocation of the data in the first storage medium is altered, the other one of the allocation of the data in the second storage medium and the allocation of the data in the first storage medium is freed.