CHAPTER 3: Setting Up and Getting Started

How it increases performance

The more drives you have in your RAID 0 array, the faster the potential drive reading performance. All hard drives have limitations on how fast they can read and write files. If half a file is stored on one RAID 0 drive and the other half on another RAID 0 drive, each drive only has to read half of the file. So, the entire file is accessed by the computer up to twice as fast (using a two-drive RAID 0 array). In a three-drive RAID 0 array, if the file is evenly distributed among the drives, each drive must read only a third of the file, and so on. If the entire file happens to be stored on only one of the drives, the file is accessed at the same speed as if it were on a standard hard drive setup. Dividing up files between multiple hard drives like this is called striping.

RAID 0

AB

C D

EF

Howit makes file storage cheaper

Because RAID 0 lets your computer see multiple hard drives as a single drive, you can install several lower capacity (less expensive) drives and have the same single-drive storage simplicity and capacity as a larger, more expensive hard drive.

Drawbacks

Unfortunately, RAID 0 lets multiple drives behave as one in another way. If part of the array fails (such as a hard drive crashing), the entire array fails. Because the drives are treated like a single drive, parts of files (including operating system files) can be spread across several drives, leaving the computer with only file fragments if one drive fails. Regular and frequent backups are critical.

Another drawback is that RAID 0 treats each hard drive as if it has the storage capacity of the smallest drive in the array. So if you have three drives (300 GB, 250 GB, and 200 GB) in a RAID 0 array, your computer only recognizes 600 GB total capacity.

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