A method, data processing system, and computer program product for managing images. A processor unit divides an image for a virtual machine into blocks. The processor unit determines whether to compress the blocks prior to transmitting the blocks to a destination for the image. In response to a determination to compress the blocks, the processor unit compresses the blocks to form a compressed set of blocks. The processor unit sends the compressed set of blocks and any uncompressed blocks remaining in the blocks to the destination for the image.