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Mercury Rack Pro Raid Review - Performance RAID 3, RAID 5
Mercury Rack Pro Raid Review - Quad Interface Hardware RAID Storage Solution
The Mercury Rack Pro offers both RAID 3 and RAID 5. Both use parity data to make disk striping (RAID 0) less vulnerable to data loss caused by a single failed drive. In fact, both RAID 3 and RAID 5 are able to continue to operate with a single drive failure, and able to rebuild the missing data when the failed drive is replaced.
The main difference between RAID 3 and RAID 5 is where the parity data is stored. In the case of RAID 3, one of the drives in the set is dedicated to holding the parity data. In the case of RAID 5, the parity data is distributed across all drives.
Because the two types of RAID levels produce very similar results, I'm only showing the results of the more popular RAID 5 here.
Here are the RAID 5 benchmark results. All results are averaged over five test sequences:
- Standard test: Sequential read - 160.809 MB/s
- Standard test: Sequential write - 116.182 MB/s
- Standard test: Random read - 21.586 MB/s
- Standard test: Random write 7.61 MB/s
- Large test: Sequential read - 253.023 MB/s
- Large test: Sequential write - 202.772 MB/s
- Extended test: Sequential read - 252.194 MB/s
- Extended test: Sequential write - 199.968 MB/s