I have 256 GB SSD drive which I don't defrag and 1 TB HDD drive that contains mainly data files, virtual machines, videos, music, etc. I basically never defrag this drive either because the defrag would take several days. Is there a small program or service that can run in the background and defrag this drive/consolidate free space on it (including moving large files around). Since the defrag is unlikely to complete in one session (I prefer to turn off the computer for nights), it would be good if it could pick up where it left off after the computer is restarted, and also defrag files as they are added or modified (downloads, VM files, etc.)? notes: I'm defragging the drive now, or at least trying to consolidate free space on it because AX64 had a problem making a backup to it, and I thought maybe its very fragmented free space was an issue. also, all my external drives are so full that I cannot just copy all the data to one of them and back to make the files contiguous.