| Level | Explanation | Advantages | Disadvantages | Remarks |
| 0 | Striping across disks | Larger I/Os or throughput Full utilization of disk array capacity Good for read & write | No fault tolerance One disk fails, entire volume fails. Cannot recover from failed disk. | Usually 2-4 drives. Applications requiring high performance but non –critical data and low cost. |
| 1 | Mirroring | Highest fault tolerance. Good for read | Higher cost | Smaller applciations with high availability |
| 0 + 1 | Striping + Mirroring | Very high reliability Good for read & write High performance | Higher cost | Samller applications with high performance |
| 2 | Inherently parallel mapping and protection technique. Mostly it is not deployed because it needs special disk futures. Disk production is not economical cost wise. | |||
| 3 | Data striped across disks. Min. 3 disks are required | Cost is lower than other redundant levels | Bottleneck for small I/O operations RAID 3 is not found on all controllers. | Large I/O request like CAD, CAM imaging. |
| 4 | Similar to Raid 3. Unlike Raid 3 it wirtes parity in a single disk. | Parity data for whole array requires just one disk. | Bottleneck for small I/O operations due to | Large file transfers |
| 5 | Calculates parity, and writes the data in stripes across disks. Rotational parity | Smaller datafiles high throughput. Even if one disk fails system will be up and runing. Reasonable cost. | Slower Write than Raid-3 and Raid-4. Write performance poor. Recovery is slow. | Very high read rate. Less write applications. OLTP File server Web server |
ORACLE - RAID MATRIX
| Oracle files | Raid Levels |
| Parameter files | 5 , 0+1 , ANY |
| Control files | 5, 0+1, ANY |
| Redo logs | 1, 0+1 |
| System Tablespace | 5,1, 0+1 |
| Temporary Tablespace | 0 |
| Rollback Tablespace | 5 |
| Data files | 5 , 0+1 |
| Index Tablespace | 5, 0+1 |
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