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Compressed and deduplicated files appear no differently than regular files to standard quota policies. However, for deduplicated files, if the quota is configured to include data-protection overhead, the additional space that is used by the shadow store will not be accounted for by the quota.
SmartQuotas reports both storage efficiency and data reduction as a ratio across the dataset as specified in the quota path field. These efficiency and data reduction ratios are for the full quota directory and its contents, including any overhead, and reflects the net efficiency of both compression and deduplication.
The ‘isi quota quotas view’ CLI command provides considerably more detailed storage capacity and efficiency metrics. These include the following:
Metric | Description |
AppLogical | The application data that can be written to the cluster, irrespective of where it is stored from. |
FSLogical | Removing sparse data (data that was always sparse, was zero block eliminated, or data that has been moved to the cloud and so on.) results in filesystem logical, which is the non-sparse data stored on the filesystem. |
AppPhysical | Data reduction techniques, such as compression and deduplication, reduce filesystem logical to application physical, or preprotected physical. This is the physical size application data on the filesystem disks, and does not include metadata, protection overhead, or data moved to the cloud. |
FSPhysical | Application physical with data protection overhead added – including inode, mirroring and FEC blocks and so on. Filesystem physical is also seen as protected physical. |
Reduction | The data reduction ratio is the amount that has been reduced from the filesystem logical down to the application physical. |
Efficiency | The storage efficiency ratio is the filesystem logical divided by the filesystem physical. |
The graphic below illustrates the relationship between the capacity, data reduction and storage efficiency elements in the OneFS storage taxonomy:
For more information about compression and inline deduplication, see the OneFS In-line Data Reduction white paper.
For more information about post-process deduplication, see the OneFS SmartDedupe white paper.