RAID 6 or RAID 10 (RAID 1, 0): What to choose?

RAID 6 and RAID 10. : Advantages and Disadvantages.


Much has been written about the need to avoid RAID 5 due to the inherent limitations set. RAID 6 provides much greater protection against data loss, especially when the data size is growing. Here the choice between RAID 5 and RAID 6 is evident in many ways. But we must remember that when you use the latter, it is necessary to make some compromises. The most important thing - it's limitations manner of execution records. For each write operation in RAID 6 requires six disk I \\ O. In RAID 5 is a total of four operations. This is a significant stumbling block to the dissemination of information in your IT-structure, correcting the balance of the input \\ output it.

Although the price has always been an important factor when buying a new data warehouse, the current stage of technology development can focus on quality rather than the quantitative aspect of the information storage. Based on these considerations, the best RAID - the decision is of course a RAID 10 (striping mirrored disks).

Evaluating the different arrays, we will not consider the capacity (assuming we have a lot of space ), and focus on the balance of the process of writing \\ reading. In this case, RAID 10 wins in two types of arrays discussed above, since it requires only a 2-step recording, as opposed to RAID 5 with 4 points record information, much more RAID 6, which imposes a limit of 6 x.
In addition,. RAID 10 has several other advantages:.

- Higher speed record. RAID 0 sets a delay of only 2.

- Quick recovery speed. Change or restore the disk is much easier and faster than RAID 6. When implementing hot backup process is very fast, so it is unlikely you will suffer from irreparable loss of two disks simultaneously.

- Can withstand the loss of multiple disks ( in some cases). It's a bit precarious position, but it is important to note. Of course, RAID 6 can withstand the loss of two disks in the array, and it is most important for those who choose it is an organization of data storage. However, the probability of simultaneous failure of two mirrored disks in a RAID 1 0 is extremely low. Therefore, if the information is properly distributed, you can theoretically withstand the loss of each disc with one side of the mirror (that is, half of all of your speakers), while continuing to work with another copy of data through your. RAID controller.

- Reduced productivity during the recovery process is minimum. When fails one of the disks in a RAID 6, the recovery process substantially reduces the overall efficiency of data storage due to the need recalculation of checksums. Recover data on RAID 10 is a relatively hidden process.

Returning to the cost of space, which is unavoidable criterion in choosing between RAID 6 and RAID 10, it is important to note that in the case of RAID 6, you ... In RAID 10, you teryaete50 % of the total capacity of the array, regardless of the number of disks. However, other benefits did say that RAID 10 is clearly wins in front of RAID 6.

If your drive is configured as RAID 6, and you do not have performance issues - no need to change everything in a matter of urgency to move to a RAID 10. All of the above should be considered when introducing new stores, assessing the feasibility of elevated levels of expenditure on RAID 10. Your choice should be a kind of a good trade-off between money and risk management needs.