File system defragmentation

If a file system has been created with a fragment size smaller than 4 KB, it becomes necessary after a period of time to query the amount of scattered unusable fragments. If many small fragments are scattered, it is difficult to find available contiguous space.

To recover these small, scattered spaces, use either the smitty dejfs command or the smitty dejfs2 command or the defragfs command. Some free space must be available for the defragmentation procedure to be used. The file system must be mounted for read-write.