RAID5 vs RAID10

RAID, or Redundant Array of Independent Disks, is a technology that allows the use of multiple low cost drives to provide superior performance, reliability, and storage capacity. There are many configurations of RAID with RAID5 and RAID10 as two examples. The main difference between RAID5 and RAID10 is their classification. RAID5 is a standard RAID level while RAID10 is a nested, or a combination of 2 standard RAID levels; namely RAID1 + RAID0.

RAID5 uses parity as a failsafe mechanism and it is spread out across the drives so that whichever drive fails, it can be reconstructed using the remaining drives and the parity data. RAID10 doesn’t use parity since it mirrors the drives with RAID1 then stripes them with RAID0. RAID10 can tolerate any number of disc failures as long as there is one left within each RAID1 level. This means that RAID10 arrays are more reliable than RAID5 since two or more disk failures automatically result to unrecoverable data in RAID5.

RAID5 is also slower than RAID10; even more so with writes than with reads. This is because the RAID5 controller needs to compute the parity before writing it to the drives. RAID5 also needs to know where the actual data and the parity are before reading. It is therefore better to use RAID10 than RAID5 for performance and reliability.

The downside of using RAID10 is cost, space, and power consumption. In RAID5, only one drive in the array is wasted to the parity. So if you have 6 drives, the total capacity would be the sum of 5 drives. In RAID10, you waste at least half of the total capacity due to mirroring; even more so if you use more than 2 drives in every RAID1 array. So there is a trade-of between reliability and space. In order to create a RAID10 array that matches the capacity of a RAID5 array, you are going to need a lot more drives. This directly translates to greater cost of owning and maintaining, greater power consumption as all the drives would be running together, and a greater amount of space needed to mount them.

Summary:

1.RAID5 is a standard RAID level while RAID10 is a nested RAID level
2.RAID5 uses parity while RAID10 doesn’t
3.RAID10 can tolerate more disc failures than RAID5
4.RAID10 is faster than RAID5
5.RAID5 is more space efficient than RAID10

Sharing is caring!