The Space Utilization by File Type chart displays the datastore usage by virtual machine files.
The Space Utilization by File Type chart is located in the Storage view of the virtual machine Performance tab.
|Virtual Disks||Amount of disk space used by virtual disk files.
Virtual disk files store the contents of the virtual machine's hard disk drive, including information that you write to a virtual machine's hard disk - the operating system, program files, and data files. The files have the extension .vmdk and appear as a physical disk drive to a guest operating system.
Note: Delta disks, which also have an extension .vmdk, are not included in this file type.
|Swap Files||Amount of disk space used by swap files.
Swap files back up the virtual machine's physical memory.
|Snapshots||Amount of disk space used by virtual machine snapshot files.
Snapshot files store information about virtual machine snapshots. They include snapshot state files and delta disk files. A snapshot state file stores the running state of the virtual machine at the time of the snapshot. It has the extension .vmsn. A delta disk file stores the updates made by the virtual machine to the virtual disks after a snapshot is taken.
|Other VM Files||Amount of disk space used by all other virtual machine files, such as configuration files and log files.
|Total Space||Amount of disk space used by the virtual machine.
total space = virtual disk space + swap file space + snapshot space + other VM file space
The datastore is at full capacity when the used space is equal to the capacity. Allocated space can be larger than datastore capacity, for example, when you have snapshots and thin-provisioned disks. You can provision more space to the datastore if possible, or you can add disks to the datastore or use shared datastores.
If snapshot files are consuming a lot of datastore space, consider consolidating them to the virtual disk when they are no longer needed. Consolidating the snapshots deletes the redo log files and removes the snapshots from the vSphere Web Client user interface. For information about consolidating the data center, see the vSphere documentation.