Dell
Parity | Data 1 | Data 2 | Data 3 | P parity | Q parity |
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Generation | Data 5 | Data 6 | P parity | Q parity | Data 8 |
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| Data 9 | P parity | Q parity | Data 11 | Data 12 |
| P parity | Q parity | Data 14 | Data 15 | Data 16 |
| Q parity | Data 17 | Data 18 | Data 19 | P parity |
| Drive 1 | Drive 2 | Drive 3 | Drive 4 | Drive 5 |
Figure 7. Example of RAID 6 (Single Virtual Disk with 5 drives)
Advantages of RAID 6
∙Can survive the loss of two disks without losing data
∙Data redundancy, high read rates, and good performance
Disadvantages of RAID 6
∙Requires two sets of parity data for each write operation, resulting in significant decrease in write performance
∙Additional costs because of the extra capacity required by using two parity blocks per stripe
∙Retrieval of parity information after a drive failure takes longer than with mirroring
5.3.5RAID 10 (Striping over Mirrored Sets)
RAID 10 combines striping and mirroring to produce large virtual disks with high performance and
Although this delivers the highest performance, the drive storage overhead is 100 percent because the entire virtual disk is mirrored. This is an excellent solution for sites that require the highest level of performance and redundancy, as well as the fastest recovery of data after a drive failure.
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