# fallocate > Reserve or deallocate disk space to files. > The utility allocates space without zeroing. - Reserve a file taking up 700MB of disk space: `fallocate --length {{700M}} {{path/to/file}}` - Shrink an already allocated file by 200MB: `fallocate --collapse-range --length {{200M}} {{path/to/file}}` - Shrink 20MB of space after 100MB in a file: `fallocate --collapse-range --offset {{100M}} --length {{20M}} {{path/to/file}}`