Administrator Guide

Supported Hardware Platforms
The following controller series support Data Reduction:
• SCv3000 Series (Supports Compression only)
• SC4020
• SC5020
• SC5020F
• SC7020
• SC7020F
• SC8000
• SC9000
Compression
Compression reduces the amount of space used by a volume by encoding data. Compression runs daily with Data Progression. To change
the time at which compression runs, reschedule Data Progression. Compression does not run with an on-demand Data Progression.
When compressed data is read, it is temporarily uncompressed in memory until the read is complete. When compression is disabled, pages
are permanently uncompressed during the next compression cycle, and the original compressed page is deleted as time and resources
permit. When a volume is deleted or a snapshot is coalesced, the related compressed data is also deleted.
Deleted data might create gaps in the compressed page, which can be filled with new compressed data. In addition, compressed pages are
defragmented during Data Progression to remove gaps and use space more efficiently.
The Compression Savings amount is determined by comparing the total amount of space saved from all compressed pages to the total
amount of used space that is eligible for compression. For example, if compression saves 1 GB on a volume with 10 GB of used space that
is eligible for compression, the amount saved is 10 percent.
Apply Data Compression to a Volume
Apply Data Compression to a volume to reduce disk space usage for that volume.
Steps
1. If the Storage Manager Client is connected to a Data Collector, select a Storage Center from the Storage view.
2. Click the Storage tab.
3. In the right pane, click Edit Settings.
The Edit Volume dialog box opens.
4. From the Data Reduction Profile drop-down list, select Compression.
5. Click OK.
Related tasks
Creating Volumes
Modifying Volumes
Deduplication
Deduplication reduces the space used by a volume by identifying and deleting duplicate pages. Deduplication requires SSD drives.
Apply Deduplication With Compression to a Volume
Apply Deduplication with Compression to reduce the size of the volume. Deduplication and compression run during daily Data Progression.
Prerequisites
Allow Data Reduction Selection must be enabled in the Preferences tab of the Edit Storage Center Settings dialog box.
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Storage Center Administration