> For the complete documentation index, see [llms.txt](https://docs.parallels.com/landing/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.parallels.com/landing/parallels-desktop-developers-guide/command-line-interface-utility/manage-virtual-machines-from-cli/virtual-machine-disk-optimization.md).

# Virtual Machine Disk Optimization

**prl\_disk\_tool** is a standalone utility (included with Parallels Desktop) used to optimize Parallels virtual machine disk space.

#### Parameters

**prl\_disk\_tool compact** \[**--buildmap**] **-hdd** <*disk\_name*> \[**--force**] \[**-comm** <*memory\_name*>]

**prl\_disk\_tool compac**t **i**,**info** **--hdd** <*disk\_name*> \[**comm** <*memory\_name*>]

The **prl\_disk\_tool compact** command removes all empty blocks from expanding Parallels virtual drives and reduces the space they occupy on your host machine. Compacting is performed by scanning file systems for unused clusters and cleaning the corresponding disk blocks. The supported file systems are NTFS, FAT16/32, ext2/ext3. You can also try to compact disks with unsupported file system types using the **--buildmap** option.


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