Command option Sample:fsutil volume allocationreport

Search command sample in the internet.It is the result.

fsutil volume allocationreport C: > report.txt    Troubleshooting tips from the IT trenches: Wherefs my disk space? - TechGenix : http://techgenix.com/wheres-my-disk-space/
fsutil volume allocationreport C:    Fsutil | Microsoft Docs : http://docs.microsoft.com/en-us/windows-server/administration/windows-commands/fsutil-volume
fsutil volume allocationreport X: >somefolder\allocation.txt    Use a New Command in Windows 8.1 to Find out how Your Disk Space is Being Used | Gizmo's Freeware : http://www.techsupportalert.com/content/use-new-command-windows-81-find-out-how-your-disk-space-being-used.htm
fsutil volume allocationreport X:    NTFS Misreports Free Space (Part 3) – Ntdebugging Blog : http://blogs.msdn.microsoft.com/ntdebugging/2014/05/08/ntfs-misreports-free-space-part-3/

search Google

https://www.google.com/#q=fsutil volume allocationreport