RAID: Something worth my time?

AwsmGy

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As of this moment, I have 2 80GB Seagate hard drives. One is 7200.8 the other is 7200.9. Now, I pretty much do everything on my computer, edit photos, watch movies/TV, music, ect. Right now all I use the .9 for is Windows and programs, the .8 has all my music and pictures on it. I've come to find that being a huge media whore allows me to fill up an 80GB hard drive FAST. I shoot pictures with a Canon 20D and generally dump up to a gig worth of shots at a time. Anyways, my question is should I just buy say...3 brand new 250GB 7200.10 HDD's and set up a RAID 5 configuration, or should I just buy a 500GB or something and have three individual HDD's.

Edit: Forgot to mention, I don't know a whole lot about RAID, I know the differences between the different types, but wouldn't have the slightest clue on how to correctly set it up without researching it.
 

candeethug

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Ok not a raid expert or aything, but I will try to help. I currently run a raid 0 array made up of 2 of the WD raptor 74gig drives for my system drive. I personally love it because it makes windows and all my programs load a lot faster. Now if you are not trying to have your system on a raid array, the only thing you would really need it for would be security (raid 1 and the like) for your storage (music, videos, whatever). Unless you are doing heavy work with video editing or 3d rendering, using your non-system drives to hold all of those files, there is really no need to run any type of RAID array that boosts speed as even IDE is fast enough to watch videos.

Now I'm not telling you what to do, but if it was my system I would rather get 1 large HD for my media rather than 3 smaller ones. I just look at it like the less hardware you have is less you have to worry about something breaking down...
 

Mondoman

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It depends on how much money you want to spend, what hardware is already in your system, how important disk latency is to you, how important disk throughput is to you, how important redundancy is to you (being able to have a single drive fail w/o losing data), how important storage space efficiency is to you, etc.
I'd start with some reading to get a better idea of what you might get into. For example, just on the issue of controllers, the following questions will come up: will you use IDE, SATA, or SCSI drives? How many drives? What level of RAID? An integrated controller or add-on card? What balance between CPU-use and controller price (i.e. cheap/built-in controllers often use the host CPU and can significantly slow things down, especially in RAID 5; OTOH, a good new SATA RAID5 controller card w/onboard processor & memory will cost $500). What bus for an add-in card (PCI or PCI-express)?
 

SuperFly03

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It is amazing how often this question comes up.

Here is a break down of your basic RAID arrays you will run into:

RAID 0: Takes a minimum of two drives, up to 4 (or more depending on your controller) and it strips the data into predetermined block sizes and alternates writing between the disks.

Advantage: higher throughput in larger file transfers, great for video editing, great for lots of random file access (think server esq situation, in general)

Disadvantage: One drive dies you lose everything, same seek times, has no affect on gaming performance, increases windows load time (you have to go through the RAID device boot sequences + windows boot sequence)

RAID 1: takes 2 drives and mirrors the data across the drives, meaning whatever it writes to one it writes to the other. Everything is duplicated, everything.

Advantage: Perfect real time data backup

Disadvantage: Wastes a full hard drive devoting it entirely to mirroring, no performance advantage, increases windows boot time, no benefit for gaming or video editing.

RAID 5: Takes a minimum of 3 drives. This is where you really need to get a separate RAID controller. The processor breaks up the data and writes the information to Drive 1, then copies it to drive 2, then the next set of information is written to drive 2 and a copy is written to drive 3, then the next bit of data is written to drive 3 and a copy is is written to drive 1, so on and so forth. The size of the array is total disks - 1. There is no dedicated backup drive in the array in the case of distributed parity (what I described). You can also have nondistributed parity, which is where there is a dedicated drive that the parity (backup information) data is written to.

Advantages: Throughput increase, though not as much as RAID 0, from what I remember. Provides more flexibility than RAID 1 while maintaining the fault tolerance of RAID 1. Great for large arrays, this is what you would typically find in a server environment (if not RAID 6).

Disadvantages: Takes alot of disks, no affect on gaming performance, increase windows load time, needs a dedicated processor for parity calculations for best performance, expensive

RAID 6: Same as RAID 5 except that the size of the array is total disks - 2 and parity information is written to two different drives. RAID 6 can tolerate 2 hard drive failures simultaneously and still not lose data.

RAID 10/01: Takes 4 disks, it is a combination of RAID 0 and 1. If it is RAID 10, the data is mirrored across two drives then stripped across the other two. If it is RAID 01, then it is stripped across two drives then mirrored across the other two drives

Notes: RAID 10/01 is generally too much effort, plus you lose two disks.

Bottom line: Most people say their RAID system is faster, which is true in select environments. You have to apply context. Hard drives are not the bottleneck in a gaming or multimedia playback context. If you are editing large video files, transferring large (and I mean gigabytes, if not terabytes) of information, or have to have MS word files open .0000001% faster, then RAID is for you. I have used RAID 1/0 and its not worth the effort.
 

happy_fanboy

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You can run raid 5 with the onboard geforce 6150 raid on the cheap 6150 motherboards, and ive done it with 3 WD 2500KS HDDs. Performance was good and it passed my failure simulation well.
All you need is 3 disks its really easy.
I used an MSI K8GM2-FID 939 motherboard with my setup.
 

happy_fanboy

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True a high end raid card will multiply performance but for the price the onboard RAID is very sweet, boards only like 85 bucks. Features were great and a monkey could do the disaster recovery. I experienced bare metal performance serving games with it.
 

AwsmGy

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What I'm more or less concerned about is A: Running out of space, and B: Some kind of failure resulting is losing pictures and music. Performance wise, I really could care less about, I know running RAID 0 really won't boost my performance enough for me to care about. Is is possible to just get another hard drive, and set two of them up in to a RAID 1 configuration and leave the 7200.9 running only my programs?
 

happy_fanboy

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RAID 5 used to be very tough to do but with Geforce 6150 its easy. With RAID 5 you can lose a disk and replace it without losing data, if you use 3 250GB drives you will have 500GB of usable space.
Bu the SINGLE MOST IMPORTANT RULE FOR RAID:
Always purchase one extra HDD at the time of purchase as a stand-by HDD. With RAID 5 you WILL lose a HD at some point and may not be able to get the same model when that happens. Always buy the exact same model HDDS for any RAID.
 

SuperFly03

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What I'm more or less concerned about is A: Running out of space, and B: Some kind of failure resulting is losing pictures and music. Performance wise, I really could care less about, I know running RAID 0 really won't boost my performance enough for me to care about. Is is possible to just get another hard drive, and set two of them up in to a RAID 1 configuration and leave the 7200.9 running only my programs?

yeah, that is perfectly acceptable. that is actually the easier way of doing it, as opposed to having the RAID array span your windows installation. All you need to do is get another identical drive and plug it is. Then, go into your BIOS, enable RAID and restart. Then you should see something the the effect of "Silcon Image RAID blah blah " (Or who ever made your RAID chip) and then the next line should be "Press Ctrl +F to enter RAID bios" again the exact msg will depend on who made your chip. Then you will boot to the RAID setup screen and just follow the onscreen guide and create a RAID 1 array. The Capacity of the RAID 1 array will be the size of on disk, obviously sense it duplicates everything hehe. I would suggest unplugging your OS drive when you are doing this just to make sure you don't select it and add it to the array, that would be very very very bad.
 

cs120ban

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Raid is fast (Excluding Raid 1)

I've been using and managing servers and currently using RAID 1, RAID 0, RAID 0+1, RAID 5 and RAID 10.

If you plan to run RAID without failures, you'll need reliable HDs and RAID cards.

I spent around
$700 on 2 RAID cards LSI 150-6
$600 on 2Raptor 150gb 16 MB
$400 on 2 Raptor 74gb 16MB
$300 on 3 RE 250GB 16MB
$1400 on 6 RE2 500GB 16MB
$400 on enclosures (Yes this matters when you try to hotswap on RAID Failures. Temperature controlled ones corrupted my entire RAID array.)

Note: I'm running in a server environment. The downtime cost more money than the Hard cost.

Raid 5 is slower than Raid 10.
Raid 0+1 is not as reliable as Raid 10.
Raid 0 is not fault tolerance.
Raid 1 is 50% fault tolerance.
Raid 10 is fast but max of 4 HD

Raid are stable with good hardware.
DO NOT RAID MAXTOR SATA HD. You'll get dead raid very often. I got raid failure of RAID 0, 1, 5, 0+1, 10 on MAXTOR SATA HD.

Even though I run RAID at work but not at home. Why waste my time on RAID? I do not share files through out a network nor stream video nor a server (too lazy to setup one).

Hardware raid cards are good. Plz stay away from Sil or onboard ones (Nvidia).