Mechanisms are provided for data transfer reduction in scale out architectures. When a compute node receives a write input/output (I/O) request for a data stream, the compute node separates the data stream into chunks and generates fingerprints for the individual chunks. Fingerprints are then sent to a scale out node and compared to fingerprints of chunks already maintained at the scale out node. Write data transfers are only made for chunks not already maintained at the scale out node. For a read I/O request for a data stream, fingerprints for chunks of the data stream are requested by the compute node from a scale out node. Fingerprints received are compared to fingerprints of chunks already maintained at the compute node and read data transfers are only made for chunks not already maintained at the compute node.