Defragmenting Virtual Disks to Improve Performance
Just like physical hard drives, virtual disks can become fragmented over time. Defragmentation reorganizes files, programs, and unused space within the virtual disk, leading to better overall performance of the virtual machine.
Keep in mind that defragmentation does not free up unused space. To reduce the size of the disk, you will need to perform a shrink operation.
Recommended procedure for performance optimization
- Run a defragmentation tool inside the virtual machine
Use Windows' built-in Defrag utility or a third-party application. - Shut down the virtual machine and defragment the virtual disk via the management interface:
- Go to VM > Settings
- Select the virtual disk to optimize
- Click Defragment
- Run defragmentation on the host system
The physical disk hosting the virtual machine files can also benefit from defragmentation, which may enhance performance further.
Warning
Defragmentation may take a long time depending on the disk size and fragmentation level.
Ensure there is enough free space on the host disk. If the virtual disk is stored as a single file, you should have at least as much free space as the file’s size. Disks split into multiple files typically require less temporary space during the process.