Volume is the basic of TNAS storage space, all of your data (such as Shared folders, documents, etc.) are stored in the volume, before starting to data storage to TNAS, you need to create at least one volume,

If the data changes frequently, the number of pieces files in file system will increase, leading to the hard disk file access performance degradation, performing file system defragmenter can improve performance,
1. TOS desktop - storage management - volume;

2. Select the executable system defragmenter volume;

(3) from the "more" drop-down menu, select the file system defragmenter;

4. Click on the confirmation;

5. File defragmentation;

6. Complete,

Note: only in "file system format" for Btrfs defragmentation can perform on the volume of file system,