A computer-implemented method, according to one embodiment, includes: maintaining a heat map monitoring table on a per volume basis for a plurality of volumes which includes a heat count for each data block in the respective volume. The data blocks in a first volume which are depended on by one or more other volumes of the plurality of volumes are identified, the first volume being specified in a deletion request. Moreover, the identified data blocks and the corresponding heat counts are copied to the respective one or more other volumes.