Understanding Space Utilization Graphs in Datastore Performance Charts

Products

• VMware vCenter Server

Issue/Introduction

VMware vCenter Datastore performance charts provide a breakdown of the types of files consuming space on a datastore. This article explains the meaning of each slice in the Space Utilization pie chart.

Note: These performance charts are historical, and do not update immediately. For current metrics, see the Storage Views tab in the vSphere Client provided by the Storage Monitoring plug-in. For more information, see the Working with Performance Statistics and Monitoring Storage Resources sections of the vSphere Basic System Administration Guide.

Resolution

To view a datastore Space Utilization chart in the vSphere Client, select the datastore, then Performance tab, Overview and select Space Utilization view.

Space consumption of a VMFS Datastore is grouped into 6 categories:

 

1. Virtual Disks: Virtual disk files store the contents of the virtual machine's hard disk drive, including information that has been written 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. Does not include Delta (redolog) disk files, which are reflected under Snapshots.
    
2. Swap Files: Virtual machine swap files augment the virtual machine's physical memory.
    
3. Snapshots: Snapshot files store information about virtual machine snapshots. They include snapshot state files and delta (redolog) disk files. A snapshot state file stores the running state of the virtual machine at the time of the snapshot, and has the extension .vmsn.
    
4. Other VM Files: Additional files used by all other files associated with a virtual machine, such as the .vmx configuration file and log files. If the virtual machine is suspended, includes the .vmss suspend state file.
    
5. Other: All other non-managed files placed on the datastore, such as documentation, backups, and ISO or Floppy images. Includes all virtual machine files which are not associated with a registered virtual machine. On ESX, includes the Service Console's virtual disk file (esxconsole.vmdk).
   
   Note: Information stored on a Datastore by Lab Manager and not associated with a registered virtual machine in vCenter Server, including virtual machine Captures, will be reflected in the Other category.
    
6. Free Space: Unallocated space available for use.

The Space Utilization Pie chart appears similar to:

 

The total space of the 6 categories matches the maximum capacity of the datastore.