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SmartQuotas has four main resources that are used in quota accounting:
Accounting resource | Description |
Physical size | Physical size includes all the on-disk storage associated with files and directories, except for some metadata objects including the LIN tree and snapshot tracking files (STFs). For deduplicated data and file clones, each file’s 8 KB reference to a shadow store is included in the physical space calculation. |
File system logical size | The file system logical size calculation approximates disk usage on typical storage arrays by ignoring the erasure code, or FEC, protection overhead that OneFS employs. For regular files, the logical data space is the amount of storage required to house a particular file if it was 1x mirrored. Logical space also incorporates a file’s metadata resources. |
Application logical size | Application logical size reports total logical data store size across different tiers, including CloudPools. This allows users to view quotas and free space as an application would view it, in terms of how much capacity is available to store logical data regardless of data reduction or tiering technology. |
Inodes | SmartQuotas counts the number of the logical inodes, allowing accounting for files without any ambiguity from hard links or protection. |
During quota configuration, these accounting options are available as enforcement limits. For example, from the OneFS WebUI:
Application logical size quotas are available in OneFS 8.2 and later. Existing quotas can easily be configured to use application logical size upon upgrading from an earlier OneFS version. The benefits of application logical size quotas include:
The following table describes how SmartQuotas accounts for a 1 KB file with the various datatypes:
Datatype | Accounting |
File: physical size | Every non-sparse 8 KB disk block that a file consumes, including protection |
File: file system logical size | Every non-sparse 8 KB disk block that a file consumes, excluding protection |
File: application logical size | The actual size of file (rather than total of 8 KB disk blocks consumed) |
CloudPools file: file system logical size | Size of CloudPools SmartLink stub file (8 KB) |
CloudPools file: application logical size | The actual size of file on cloud storage (rather than local stub file) |
Directories | Sum of all directory entries |
Symlinks | Data size |
ACL and similar | Data size |
Alternate data stream | Each ADS is charged as a file and a container as a directory |
The following figure shows each method of accounting for a 1 KB file.
Logical size reports 8 KB, or one block, physical size reports 24 KB (file with 3x mirroring protection), and application logical shows the actual size of 1 KB.
Other resources that are encountered during quota accounting include: