Releasing a portion of mass memory, relocating memory blocks stored in boot locations of the target software image to the released portion, storing the boot blocks into corresponding boot locations, booting the data-processing entity from the boot blocks in the corresponding boot locations thereby loading a streaming function, and serving each request of reading a selected memory block of the target software image by the streaming function, the streaming function downloading the selected memory block from the external source and storing the selected memory block into the released portion when the selected memory block is not available in the mass memory, or retrieving the selected memory block from the mass memory otherwise.