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Table Of Contents
- 1 Introduction to member RAID policies
- 2 RAID policy availability and performance comparisons
- 3 Setting the member RAID policy
- 4 Displaying the RAID level space distribution
- 5 PS Series array disk layout
- 6 Converting or migrating from a member RAID policy
- 7 Summary
- A 12-Disk PS Series array RAID configurations
- B 14-Disk PS Series array RAID configurations
- C 16-Disk PS Series array RAID configurations
- D 48-Disk PS Series array RAID configurations
- E 42 or 84-disk PS Series RAID configurations
- F Technical support and resources
16 Dell PS Series Storage: Choosing a Member RAID Policy | TR1020 | v 4.7
2.5 Relative capacity utilization by RAID policy
Selection of the RAID policy impacts the capacity utilization of the RAID set in the array. Some RAID levels
are more efficient and provide greater usable capacity for a given amount of raw capacity. The graph below
illustrates the relative capacity utilizations of the various RAID policies supported by PS Series arrays. These
metrics are normalized to RAID 50 (which is depicted as 100%).
Key observation: As illustrated, parity RAID policies (RAID 50, RAID 6, and RAID 5) offer comparable
utilization, whereas RAID 10 with mirroring offers less capacity in comparison.
Relative capacity by RAID policy
100%
59%
100%
108%
0%
20%
40%
60%
80%
100%
120%
RAID 6 RAID 10 RAID 50 RAID 5