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I thought it might be nice to recap the characteristics of the possible RAID configurations. |
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Please feel free to correct any points that are incorrect or inaccurate. |
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|
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I was thinking of comparing the characteristics of various RAID configurations using 4 250G disks. |
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(4) Disk RAID1: |
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|
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Total Array Capacity: 250G |
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Reading Throughput: <= 4 x a single drive read cap. |
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1 file can be read simultaneous 4 times |
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or 4 separate file can be read simultaneously |
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Write Throughput: <= a single drive write cap. |
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Fault tolerance: can survive 3 disk failures |
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|
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|
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(4) Disk RAID0: |
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|
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Total Array Capacity: 1000G |
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Reading Throughput: <<= 4 x a single drive read cap. |
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1 file can be read at-most 1 time |
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or 4 separate file can be read simultaneously |
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Write Throughput: <= 4 x a single drive write cap. |
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Fault tolerance: can survive 0 disk failures |
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|
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|
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(4) Disk RAID5: |
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|
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Total Array Capacity: 750G |
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Reading Throughput: <= 2 x a single drive read cap. (similar to RAID0) |
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1 file can be read at-most 1 time |
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or 4 separate file can be read simultaneously |
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Write Throughput: <= 1 x a single drive write cap. |
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Fault tolerance: can survive 1 disk failures |
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|
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|
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(4) Disk RAID10 --Layout=n(near): |
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functions similar to a RAID1&0 but more closely |
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follows the pattern of a RAID1 i.e. better read preformance |
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than write preformance |
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|
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|
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Total Array Capacity: 500G |
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Reading Throughput: <= 4 x a single drive read cap. (similar to RAID0) |
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1 file can be read at-most 2 times |
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or 4 separate file can be read simultaneously |
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Write Throughput: <= 2 x a single drive write cap. |
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Fault tolerance: can survive at most 2 disk failures |
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|
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|
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(4) Disk RAID10 --Layout=o(offset): |
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functions similar to a RAID1&0 but more closely |
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follows the pattern of a RAID0 i.e. better write preformance |
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than read preformance |
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|
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|
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Total Array Capacity: 500G |
| 57 |
Reading Throughput: <= 4 x a single drive read cap. (similar to RAID0) |
| 58 |
1 file can be read at-most 2 times |
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or 4 separate file can be read simultaneously |
| 60 |
Write Throughput: <= 2 x a single drive write cap. |
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Fault tolerance: can survive at most 2 disk failures |
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|
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|
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(4) Disk RAID10 --Layout=f(far): |
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functions similar to a RAID1&0 but more closely |
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follows the pattern of a RAID1 i.e. better read preformance |
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than write preformance |
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I am not sure sure how this differs from |
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--Layout=n(near) |
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|
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|
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Total Array Capacity: 500G |
| 73 |
Reading Throughput: <= 4 x a single drive read cap. (similar to RAID0) |
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1 file can be read at-most 2 times |
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or 4 separate file can be read simultaneously |
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Write Throughput: <= 2 x a single drive write cap. |
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Fault tolerance: can survive at most 2 disk failures |
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|
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Regards, |
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|
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Richard Broersma Jr. |
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-- |
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