Question: I’ve heard about and read about RAID throughout the years and understand it theoretically as a way to help e.g. server PCs reduce the chance of data loss, but now I am buying a new PC which I want to be as fast as possible and have learned that having two drives can considerably increase the perceived performance of your machine.
In the question Recommendations for hard drive performance boost, the author says he is going to RAID-0 two 7200 RPM drives together. What does this mean in practical terms for me with Windows 7 installed, e.g. can I buy two drives, go into the device manager and “raid-0 them together”?
I am not a network administrator or a hardware guy, I’m just a developer who is going to have a computer store build me a super fast machine next week. I can read the wikipedia page on RAID but it is just way too many trees and not enough forest to help me build a faster PC:
?
RAID-0: “Striped set without parity” or ?”Striping”. Provides improved ?performance and additional storage but ?no redundancy or fault tolerance. ?Because there is no redundancy, this ?level is not actually a Redundant ?Array of Inexpensive Disks, i.e. not ?true RAID. However, because of the ?similarities to RAID (especially the ?need for a controller to distribute ?data across multiple disks), simple ?strip sets are normally referred to as ?RAID 0. Any disk failure destroys the ?array, which has greater consequences ?with more disks in the array (at a ?minimum, catastrophic data loss is ?twice as severe compared to single ?drives without RAID). A single disk ?failure destroys the entire array ?because when data is written to a RAID ?0 drive, the data is broken into ?fragments. The number of fragments is ?dictated by the number of disks in the ?array. The fragments are written to ?their respective disks simultaneously ?on the same sector. This allows ?smaller sections of the entire chunk ?of data to be read off the drive in ?parallel, increasing bandwidth. RAID 0 ?does not implement error checking so ?any error is unrecoverable. More disks ?in the array means higher bandwidth, ?but greater risk of data loss.
So in plain English, how can “RAID-0” help me build a faster Windows-7 PC that I am going to order next week?
Answer: A RAID-0 configuration utilizes 2 separate hard disks and writes “chunks” of data to each one to minimize actuator movement and read/write data faster (each arm does half the work in a sense). The caveat with this is that there is a lack of fault tolerance – if one drive dies, all of your data is gone. And since there is 2 drives handling your data, the chances of losing your data is basically doubled. You may want to look into RAID1+0, which give you speed benefits as well as fault tolerance. You can swap in another disk upon failure and have the other disks rebuild it.
The RAID-0 image from wikipedia domonstrates it well:
imagine the disks are showing a file called A.txt. Now, imagine each section as a 4096-byte cluster for example. Each disk is holding roughly 16384 bytes of this text file, and if one disk dies, there is no way to recover the other half.
If you are limiting yourself to 2 disks, I’d suggest only doing the RAID-0 configuration on the operating system. Any files important to you should be stored on separate media such as an external drive, or if it was a possibility, 1 more hard drive. If it meant the difference between having a fast machine without fault tolerance, or having a slower machine with my files safe, I’d choose a slower machine. For me at least, I’d rather be safe than sorry.