RAID is short for redundant array of independent disks which is a fundamental of data protection. It combines two or more hard disks drives forming as disk array group to have higher level performance. Compared with a single hard disk, RAID can strength tolerance fault, enhance integration, increase capacity and so on. RAID has many variants such as RAID 5, RAID 0, RAID 1, RAID 10, and RAID 3.
- RAID 0
RAID 0 is also called disk stripe. For RAID 0 written data is across multiple disks so it can improve performance, but there is no fault tolerance. If a disk fails, all the data will be lost.
- RAID 1
RAID 1 is known as disk mirroring which has fault tolerance and the data can be copied simultaneously from one disk to another. A minimum of two disks is required for RAID 1. But for RAID 1, it cuts total disk capacity in half.
- RAID 3
RAID 3 is similar to RAID 5, except it needs a dedicate parity drive. RAID 3 is widely in specialized database or processing environments.
- RAID 5
RAID 5 is the most common used among business Servers. It has better performance and fault tolerance. With DAID 5, parity is generated and rotated around the data disks. The minimum of disk is three.
- RAID 10
RAID 10 combines RAID 1 with RAID 0. It has the best performance, but high price. The minimum of disk is four.
SSD with RAID
SSD disk is becoming more and more popular due to their outstanding features such as speed and durability in laptop and desktop. However, with the development of technology, these features can’t demand the need of the users. So people try to find a better way for their data. Fortunately, there is a better way that SSDs can offer great performance in Windows and servers when SSDs are combined together putting into RAID arrays. In this way RAID storage achieves two main objectives:
- Make disk drives be redundant. When one fails the system will still can work and without data lose.
- Increase the performance of I/O. the different type of RAID can offer different redundancy, performance, capacity.
Benefits of Using SSD RAID
There are many reasons for you to choose SSD RAID. For example, A PCIe solid-state storage card is widely being used to improve application and storage performance in Server, but it is a DAS model which translates to a single point of failure. In order to avoid losing data, a RAID 1 is the most suitable for you.
There are built-in RAID controllers in today’s desktops and workstations. But these RAID arrays are configured in a separate RAID BIOS accessible on system boot-up. You can use two SSDs in a RAID 0 stripe to improve the drive performance at a minimal cost. Besides, you can use two SSDs and a RAID 1 to run your drive when one of them fails.
For servers, SSDs are the best chosen for small dataset applications where need high IO performance or for an application where a user designates a caching area on high-speed storage for temporary database files and frequently accessed tables. While for desktops and workstations, which configure a small multi-drive RAID array can offer large benefit in overall system performance and accelerate applications that are IO bound by slow hard drives. It is easy for RAID arrays to improve performance and reliability.
Although SSDs have become popular among users, the performance of them can also be improved under the help of RAID. When combine SSD with RAID, they can promote each other and help you take full advantage of SSD. After using SSD for a couple of months, it is not uncommon to get low disk space. But do you really used up all space? See also SSD trim to learn more about data write and steps to enable trim support.