A method and apparatus is used to divide a storage volume into shards. The division is made using a directed graph having a vertex for each block in the storage volume and directed-edges between pairs of vertices representing a shard of blocks, associating a weight with each directed edge that represents the dissimilarity for the shard of blocks between the corresponding pair of vertices, selecting a maximum number of shards (K) for dividing the storage volume, identifying a minimum aggregate weight associated with a current vertex for a combination of no more than K shards, performing the identification of the minimum aggregate weight for vertices in the directed graph, and picking the smallest aggregated weight associated with the last vertex to determine a sharding that spans the storage volume and provides a minimal dissimilarity among no more than K shards of blocks.