When using compression and deduplication:
- I/O performance to data with compression and deduplication is degraded. Verify the performance by utilizing best practices before using the capacity saving function.
- Because approximately 10% is used for metadata and garbage data, capacity saving should be applied only when the result is expected to be 10% or higher.
- In deduplication and compression, processing is performed per 8 KB. Therefore, if the block size of the file system is an integral multiple of 8 KB, capacity saving is likely to be effective.
- The capacity saving function is not a good fit for high-write workloads. If the write workload rate is higher than garbage collection throughput, Cache Write Pending increases, causing performance degradation. Contact customer support to determine the garbage collection throughput for your configuration.
If you want to perform fast operations of logical data backup, archiving, or utilization of replicated data, take snapshot data by using Thin Image Advanced with DRS-VOLs. Thin Image Advanced enables the fast operations of taking snapshot data by using metadata with storage location information. This table shows examples of combinations of functions in software products applied to take snapshot data.
| Combination of functions in software products | Capacity saving function | Description |
|---|---|---|
| DRD-VOLs with capacity saving enabled by using dedupe and compression and ShadowImage | Deduplication and compression | The data copy operation takes a long time to process because deduplication and compression is performed after the user data copy operation. |
| DRS-VOLs and Thin Image Advanced |
Deduplication and compression Deduplication and compression are effective for a P-VOL and snapshot data of Thin Image Advanced. |
|