Compare RAID levels according to their capabilities.
The following information provides data redundancy, usable disk
capacity, read performance, and write performance for each RAID level.
Table 1. RAID level summaryRAID level |
Data redundancy |
Usable disk capacity |
Read performance |
Write performance |
Min/Max devices per array |
RAID 0 |
None |
100% |
Very good |
Excellent |
1/18 |
RAID 5 |
Very good |
67% to 94% |
Very good |
Good |
3/18 |
RAID 6 |
Excellent |
50% to 89% |
Very good |
Fair to good |
4/18 |
RAID 10 |
Excellent |
50% |
Excellent |
Very good |
2/18 (even numbers only) |
- RAID 0
- Does not support data redundancy, but provides a potentially higher
I/O rate.
- RAID 5
- Creates array parity information so that the data can be reconstructed
if a disk in the array fails. Provides better capacity than RAID level
10 but possibly lower performance.
- RAID 6
- Creates array "P" and "Q" parity information so that the data
can be reconstructed if one or two disks in the array fail. Provides
better data redundancy than RAID 5 but with slightly lower capacity
and possibly lower performance. Provides better capacity than RAID
level 10 but possibly lower performance.
- RAID 10
- Stores data redundantly on mirrored pairs to provide maximum protection
against disk failures. Provides generally better performance than
RAID 5 or 6, but has lower capacity.
Note: A two-drive RAID level
10 array is equivalent to RAID level 1.