RAID level comparison
Basic RAID array
| RAID |
0 |
1 |
5 |
6 |
| HDD |
minimum |
2 |
2 |
3 |
4 |
| failure protection |
- |
n -1 |
1 |
2 |
| Performance |
read |
high |
medium |
medium |
medium |
| write |
high |
low |
low |
low |
| Degraded |
read |
- |
medium |
low |
low |
| write |
- |
medium |
low |
low |
| Capacity utilization |
100% |
≤ 50% |
67 - 94% |
50 - 88% |
Combined RAID array
| RAID |
0+1 |
1+0 |
5+0 |
6+0 |
5+1 |
6+1 |
| HDD |
minimum |
4 |
4 |
6 |
8 |
6 |
8 |
| failure protection |
1 |
1+1 |
1+1 |
2+2 |
1+array |
2+array |
| Performance |
read |
medium |
high |
high |
high |
medium |
medium |
| write |
medium |
medium |
medium |
medium |
low |
low |
| Degraded |
read |
medium |
medium |
medium |
medium |
low |
low |
| write |
medium |
medium |
medium |
medium |
low |
low |
| Capacity utilization |
50% |
50% |
67 - 94% |
50 - 88% |
33 - 47% |
25 - 44% |
14
years
257
countries
710k
users
4659k
calculations
