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RAID 5 Vs. RAID 10
There is often a comparison between RAID 5 and RAID 10 and a debate on the difference between RAID 5 and RAID 10. This article has thus been written, to present the RAID 5 vs RAID 10 comparison. But before we start with the RAID 5 vs RAID 10 comparison, we need to know what is RAID?
RAID 5 vs RAID10
Data Loss and Data Recovery
Let us start off by having RAID 5 explained. In RAID 5, the data backup of any one of the disks is created. If there are 5 disks, in the storage system, then 4 of the disks will be used for storing the data and one of the disks will be used for keeping the backup of any one of the hard disks. If one of the disks in the array fails, then the data can be recovered, but in the event of a second disk failure, the recovery is not possible. RAID 10 on the other hand is a combination of RAID 0 and RAID 1. In a RAID 10 storage scheme, an even number of disks is required. Each disk array has a disk array, which is a mirrored set of the former. In RAID 10, data recovery of all but one disk can be performed. In the case of a disk failure, all the remaining disks can be used effectively without any impact on the storage scheme.
Performance
The RAID 5 performance in the read operations is quite appreciated, though its write operation is quite slow, as compared to RAID 10. RAID 10 is thus used for systems which require high write performance. Hence, it is very obvious, RAID 10 is not used for systems like heavy databases, which require high speed write performance.
Redundancy
The RAID 10 arrays are more data redundant than the RAID 5 arrays. This makes RAID 10 an ideal option for the cases where high data redundancy is required.
Architectural Flexibility
RAID 10 provides more architectural flexibility, as compared to RAID 5. The amount of free space left is also minimized, if you use a RAID 10 data storage scheme.
Controller Requirement
RAID 5 demands a high end card for the data storage performance. If the purpose of the RAID 5 controller is being solved by the operating system, then it will result in the slowing down of the performance of the computer. In case of a RAID 10 controller, any hardware controller can be used.
Applications
RAID 10 finds a wide variety of applications. Systems with RAID 0, RAID 1 or RAID 5 storage schemes are often replaced with a RAID 10 storage scheme. They are mainly used for medium sized databases. RAID 5 disks are primarily used in the processes that require transactions. Relational databases are among the other fields that run very well under a RAID 5 storage scheme.
also
http://www.tomshardware.co.uk/forum/page-244551_14_0.html