IDE Raid - Performance Vs Risk or Corruption

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Could someone give me some advice on IDE raid, Increase in Performance vs Chances of data corruption. Thanks
 

LTJLover

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Dec 31, 2007
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I can tell you that I used to have a Promise RAID setup in my machine. I had a bunch of old Maxtor drives that were too small and slow to count for anything so I RAIDed four of them together. Worked well, giving me a decent backup drive. I never had any problems with it getting corrupted or anything. Only problem was the heat buildup of having 6 hard drives stacked up. I might buy the Abit KT7 RAID in a few weeks and I intend to put two IBMs on the ATA100 RAID. I hear it kicks butt. I wouldn't worry about data corruption. Just back up your important stuff once a month or so. I use my CDR to make a backup.

Jon
"Water-Cooled CPU Runner"
 
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you should have no problems. raid 0(stripe) takes the stuff being written to the drives and brakes it up depending how many drive, 2 then half to one drive and the other half to the second drive.

This effectively gives you 80% increase in speed. Its not twice as fast as a one drive because time has to be taken in spliting the info then sending it out to they apropriate drive.

Down side, unless your mirroring(raid 1) that stripe. if you loose one of the drives you loos all of the data. The mirror would be your backup.

Any pls correct me if I'm wrong. I only know the theory, have never tried it, but friends have.

I recommend it and will will be doing it my self on my next system. Two 60gigs or better in raid 0 for a video editing unit.

Take care.
 
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It all depends on the level of raid you wich to use. First off, there should never be a consideration of data coruption as sonething normal. In the mass storage industry, this is considered the worst thing. It can happen, but is not a normal thing, or confined to one type of technology.
With raid, the tradeoffs are price vs. performance vs. loss of data. Raid was originally designed to be a way to lower the mean failure time of a logical disk. Hence the name RAID (Redundent Array of Inexpensive Disks). The concept behind levels 1-5 is that you can lose one disk, and still have full access to your data. This way, instead of one large disk, you could make up the same size with smaller disks and lower your mean time to failure.
For normal users, there are 3 levels of RAID to consider:

0) this will stripe data across two or more disks without any loss protection. This is the fastest RAID, and if you lose one disk, you tend to lose all data. This also has the highest risk of failure (there is a calculation you do that pretty much shows that for every disk you add, you increase the chance of a failure... makes sense, you have several moving parts now).

1) Disk mirroring. This treats two hard drives as one. When you write to the disk, to makes a copy of the data, and writes the same data to both disks. So writes are slower. Reads can be done from both disks (just like a two disk RAID 0), so reads are faster then a single disk. This also offers the protection of if one disk goes out, the other has all the data, and is still working. This is the most expensive RAID (2 disks for each logical disk), but is that fastest raid that offers protection for data loss.

5) Disk striping with parity. This is simular to RAID 0, in that is stripes data across two or more disks. The difference is that there is an extra disk that is used for parity (actually the parity can be spread across multiple disks). This also allows one disk to go out, and still allow full access to all data. The benifit here, is that you can have 6 disks, and get a logical disk that is the size of 5 of them, vs. with RAID 1, you would get a logical disk the size of 3 of them. So you get more space (i.e. cheaper). The downfall, is that this is the slowest raid as all data has to have a parity calculated for it (they use the XOR operation).

So, RAID 0 is fast, and with the stability of drives today, not that bad of a risk. Just make sure you have enough cooling for the disks. Heat is the worst for making them fail, and if you are going to risk a raid 0, lets not encourage the drives to fail.
 
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Hard Drive physical failure are quite rare. Of course, I wouldn't play around with my precious data, so be sure to do backups periodically, no matter what you do.