[ The PC Guide | Systems and Components Reference Guide | Hard Disk Drives | Hard Disk Performance, Quality and Reliability | Redundant Arrays of Inexpensive Disks (RAID) ] Why Use RAID? Benefits and Costs, Tradeoffs and Limitations RAID offers many advantages over the use of single hard disks, but it is clearly not for everyone. The potential for increased capacity, performance and reliability are attractive, but they come with real costs. Nothing in life is free. In this section I take an overview look at RAID, to help explain its benefits, costs, tradeoffs and limitations. This should give you a better idea if RAID is for you, and help you to understand what RAID can do--and what it can't do. As you read on, it's essential to keep in mind that with RAID, it's definitely the case that "the devil is in the details". Most common blanket statements made about RAID like "RAID improves availability" or "RAID is for companies that need fast database service" or "RAID level 5 is better than RAID level 0" are only true at best part of the time. In almost every case, it depends. Usually, what RAID is and what it does for you depends on what type you choose and how you implement and manage it. For example, for some applications RAID 5 is better than RAID 0; for others, RAID 0 is vastly superior to RAID 5! There are situations where a RAID design, hardware and software that would normally result in high reliability could result instead in disaster if they are not properly controlled.
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