B-RAID Level Comparison Table
Appendix B: RAID Level Comparison Table
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RAID | Description |
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| M i n . | Max. | Capacity | Fault Tolerance |
| Data |
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| I/O | ||
Level |
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| Drives | Drives |
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| Transfer Rate |
| Request Rates | |
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0 | Also known as striping | 1 | 5 | ( N ) | No fault tolerance | Very High |
| Very High for | ||||||
| Data | distributed | across multiple |
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| Both Reads and Writes | |
| drives in the array. There is no data |
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| protection |
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1 | Also known as mirroring. | 2 | 5 | 1 Disk | Greater | than | RAID | Reads are higher |
| Reads are twice faster | ||||
| All data replicated on 2 Separate |
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| 3,5 |
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| Than a single disk; | than a single disk; | |||||
| disks. This is a high availability |
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| Writes | similar | to a | Write are similar to a | |||
| Solution, |
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| single disk |
| single disk. | ||
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10 | Also | known as | 4 | 5 | ( N / 2 ) | Greater | than | RAID | Transfer | rates | more | Reads are twice faster | ||
| Parity. Data and parity information |
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| Disks | 3,5 |
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| similar to RAID 1 than | than a single disk; | |||||
| is subdivided and distributed across |
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| RAID 0 |
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| all disks. Parity must be equal to the |
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| Writes are similar to a | |||
| smallest disk capacity in the array. |
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| single disk. | |||
| Parity | information | normally stored |
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| on a dedicated parity disk. |
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3 | Also | known as | 3 | 5 | ( N - 1 ) | Lower than RAID 1, | Reads are similar to | Reads are approximately | ||||||
| Parity. Data and parity information |
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| Disks | 10 |
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| twice as fast as a single | |||
| is subdivided and distributed across |
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| greater than a single |
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| disk; | |||||
| all disks. Parity must be equal to the |
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| drive |
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| Writes are slower than |
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| smallest disk capacity in the array. |
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| a single disk |
| Writes are similar to a | ||||
| Parity | information | normally stored |
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| single disk. | |
| on a dedicated parity disk. |
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5 | Also | known | 3 | 5 | ( N - 1 ) | Lower than RAID 1, | Reads are similar to | Reads are similar to | ||||||
| Distributed Parity. |
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| Disks | 10 |
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| RAID 0; |
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| RAID 0; | ||
| Data and parity information is |
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| greater than a single |
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| subdivided and | distributed across |
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| drive |
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| Writes are slower than | Writes are slower than a | ||||
| all disks. Parity must be equal to the |
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| a single disk |
| single disk. | ||||
| smallest disk capacity in the array. |
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| Parity | information | is distributed |
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| across member disks. |
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RAIDBank5 Owner’s Manual | 38 |