MSFT_DedupVolume class

Article
05/31/2018

Represents a volume that has data deduplication metadata.

The following syntax is simplified from MOF code and includes all inherited properties.

Syntax

[dynamic, provider("DeduplicationProvider"), ClassVersion("1.0"), AMENDMENT]
class MSFT_DedupVolume
{
  String  VolumeId;
  String  Volume;
  boolean Enabled;
  boolean DataAccessEnabled;
  boolean NoCompress;
  boolean Verify;
  boolean OptimizeInUseFiles;
  boolean OptimizePartialFiles;
  uint32  UsageType;
  uint32  MinimumFileAgeDays;
  uint32  MinimumFileSize;
  uint32  ChunkRedundancyThreshold;
  uint32  InputOutputScale;
  string  ExcludeFolder[];
  string  ExcludeFileType[];
  string  ExcludeFileTypeDefault[];
  string  NoCompressionFileType[];
  uint64  Capacity;
  uint64  FreeSpace;
  uint64  UsedSpace;
  uint64  UnoptimizedSize;
  uint64  SavedSpace;
  uint32  SavingsRate;
};

Members

The MSFT_DedupVolume class has these types of members:

Methods
Properties

Methods

The MSFT_DedupVolume class has these methods.

Method	Description
Disable	Disables further data deduplication activity on one or more volumes.
Enable	Enables deduplication on the specified volumes by using default settings.
ExpandFile	Reverts the deduplication process on a set of deduplicated files. Windows Server 2012: This method is not supported until Windows Server 2012 R2.

Properties

The MSFT_DedupVolume class has these properties.

Capacity

Data type: uint64
Access type: Read-only

The capacity of the volume, in bytes.

ChunkRedundancyThreshold

Data type: uint32
Access type: Read/write

Specifies the number of identical chunks of data that are encountered during deduplication before the server creates a redundant copy of that chunk of data. Adding redundancy to the most referenced chunks of data increases the reliability of the system. Deduplication detects corruptions, and the deduplication scrubbing job restores the corrupted chunks from a redundant copy if available. The default value is 100 for identical chunks before a redundant copy is made. This property cannot be set to less than 20.

DataAccessEnabled

Data type: boolean
Access type: Read-only

If True, data access is enabled.

Enabled

Data type: boolean
Access type: Read-only

If True, deduplication is enabled on this volume.

ExcludeFileType

Data type: string array
Access type: Read/write

The list of file name extensions to exclude from data deduplication and optimization.

ExcludeFileTypeDefault

Data type: string array
Access type: Read/write

Default list of file name extension types to exclude from data deduplication and optimization.

Windows Server 2012: This property is not supported until Windows Server 2012 R2.

ExcludeFolder

Data type: string array
Access type: Read/write

The list of root folders under which all files are skipped during data deduplication and optimization. Full paths are accepted; however, mounted folders are ignored because the mounted folders can change after configuration.

FreeSpace

Data type: uint64
Access type: Read-only

The amount of free space on the volume, in bytes.

InputOutputScale

Data type: uint32
Access type: Read/write

The maximum amount of I/O parallelism to use when optimizing the volume. This value can range from "1" to "36".

Windows Server 2012 R2 and Windows Server 2012: This property is not available before Windows Server 2016.

MinimumFileAgeDays

Data type: uint32
Access type: Read/write

Optimizes files that have not been accessed in the specified number of days. If the last access time is not available, then the last modified time is used.

MinimumFileSize

Data type: uint32
Access type: Read/write

Specifies the minimum size threshold, in bytes, for files to be optimized. Files that do not meet this minimum threshold are not optimized.

NoCompress

Data type: boolean
Access type: Read/write

If True, the data are not to be compressed after deduplication.

NoCompressionFileType

Data type: string array
Access type: Read/write

The list of file types to exclude from compression. These file types are deduplicated but not compressed, because typically the file format is already compressed.

OptimizeInUseFiles

Data type: boolean
Access type: Read/write

If True, files in use are optimized.

Windows Server 2012: This property is not supported until Windows Server 2012 R2.

OptimizePartialFiles

Data type: boolean
Access type: Read/write

If True, portions of files that have been modified recently are not optimized. This property is controlled by the MinimumFileAgeDays parameter.

Windows Server 2012: This property is not supported until Windows Server 2012 R2.

SavedSpace

Data type: uint64
Access type: Read-only

Saved space is the difference between the logical size of the optimized files and the logical size of the store, which is the deduplicated user data plus deduplication metadata. Note that this number remains unchanged as users delete files from or add new files to the volume until you run an optimization job or execute the Update method of the MSFT_DedupVolumeStatus class. This number is most accurate after an optimization job runs or the Update method is executed.

SavingsRate

Data type: uint32
Access type: Read-only

The ratio of saved space from deduplication to the logical size of all of the files on the volume and is expressed as a percentage. Note that this number remains unchanged as users delete files from or add new files to the volume until you run an optimization job or execute the Update method of the MSFT_DedupVolumeStatus class. This number is most accurate after an optimization job runs or the Update method is executed.

UnoptimizedSize

Data type: uint64
Access type: Read-only

The total logical size of all files on the volume, in bytes. This includes all files, optimized and non-optimized. Note that this number will remain steady as users delete optimized files from the volume-until you run an optimization job or execute the Update method of the MSFT_DedupVolumeStatus class. This number is most accurate after an optimization job runs or the Update method is executed.

UsageType

Data type: uint32
Access type: Read-only

The type of data to store on the volume.

Windows Server 2012: This property is not supported until Windows Server 2012 R2.

The possible values are:

Default (1)

General purpose files shares. This is the default value.

HyperV (2)

Hyper-V storage.

Backup (3)

Backup storage.

Windows Server 2012 R2 and Windows Server 2012: This value is not available before Windows Server 2016.

UsedSpace

Data type: uint64
Access type: Read-only

The amount of used space on the volume, in bytes.

Verify

Data type: boolean
Access type: Read/write

If True, a byte-for-byte verification is performed for each duplicate chunk that is detected during optimization rather than relying on a cryptographically strong hash. We recommend to set this property to false.

Volume

Data type: String
Access type: Read-only

A drive letter, for example, "D:", or volume GUID path for the volume.

VolumeId

Data type: String
Access type: Read-only
Qualifiers: key

A volume GUID path for the volume. A volume GUID path is a string of the form "\\?\Volume{GUID}\" where GUID is a GUID that identifies the volume.

Examples

For an example that uses the MSFT_DedupVolume class, please see Data deduplication backup and restore sample.

Requirements


Minimum supported client	None supported
Minimum supported server	Windows Server 2012
Namespace	Root\Microsoft\Windows\Deduplication
MOF	DeduplicationProvider.mof
DLL	DdpWmi.dll

MSFT_DedupVolume class

Syntax

Members

Methods

Properties

Examples

Requirements

See also

Additional resources