How often does RAID 0 really fail?

[fetuchin]

The answer is YES, IT FAILS.
My raid 0 failed a couple of years ago and I promised myself i would never use it again. Or at least not as raid 0 alone but with four hds at raid 0+1.
On the other hand, the advantages are not spectacular, but they are REAL, and you perceive real-world benefits in speed terms while using it.
Maybe the right choice would be using it only for applications and/or data you would not have any difficulty replacing or reinstalling and NEVER NEVER EVER for relevanta data, unless you configure it as 0+1 but that means not less than four hds.
and about statistics... it does not matter wether it is 1 out of 100 or 1 out of 10000, because when it affects you, if it fails, it's 100%.
Anyway you can try to mount a deffective hd on purpose on your system, because statistically it is very unlikely that two hds fail simultaneously on the same system

 

[Cogman]

Originally posted by: Riverhound777
If you want the "increase in speed" from RAID-0, use RAID-5. It isn't like hard drives are that expensive these days.

I second that motion, RAID 5 is a bit more unique then RAID-0 because the more Hard-Drives you have, the less likely a failure is going to take out your system.

 

[bob4432]

Originally posted by: Sunner

Originally posted by: LazyGit

Originally posted by: Sunner
I'd say by far the most common misconception with RAID0 is that it'll give your average user a big performance boost in day to day tasks.

You're not the first person on here to say that. What is the basis for this? I'm looking to build a RAID0 myself in the hope that it will speed up load times for my OS and programs as well as speed up file transfers and unRARing. Is that what you would call 'average use'? Is a RAID0 not going to help in those situations?

If you have a task that's bound by sustained transfer rates, RAID-0 will help substantially.
Transfers of large files(a DVD image for example), un-rar'ing large archives(presuming you don't get CPU bound there), etc are good examples of this.
Load times for most things aren't very dependent on STR, access times will be more important here.

Average use would be, booting your computer, opening your browser, office app, whatever, play a game or two, maybe watch a movie, etc etc.
If you spend much of your time waiting for WinRAR to finish decompressing DVD images and such, yeah, you'll benefit from it.

thus the reason i have a non raid, single 15k.5 (just 1 drive which nearly = 2 regular 7.2k hdd in str) as my storage drive and another 15k drive as my os/app/game drive

 

[Sunner]

Originally posted by: Idontcare
I can't wait for people to realize that having 2 cores instead of 1 core means your computer is twice as likely to start corrupting data and killing itself.

Same for those 2 platter hard-drives, everyone knows you must go with single-platter to avoid data loss.

Oh and sucks for you if you do dual-channel RAM...everyone knows your likelihood of loosing all your data (corrupted on its way to your single-platter hard-drive after being processed on your single-core processor) is twice that over the smarties who use single-chip DDR memory (no 8 chip or 16 chip sticks in their boxes, that would be dumb) in single-channel mode.

If you are worried about Raid-0 dying (and you should be) then you should be worried about your single hard-disk dying, in either case you lost your data whether it be in 4 months (Raid-0 example) or 8 months (single-drive example). Either case you are a moron for not having a proper backup strategy in place.

Get used to losing reliability. And take off your tinfoil hats because you will be using quad-core chips next year or soon thereafter...OMG 4 times the probability of any one of those cores causing data corruption!!!! SkY IS FALLING!!!!

Slight difference being, the vast majority of people won't benefit from RAID-0, the vast majority of OEM's won't preinstall computers with RAID-0, etc etc.
My parents won't benefit much from a dual core CPU, nor RAID-0, but some day when their current 1.3 GHz Celeron fails, they'll more than likely get a DC CPU whatever they buy, getting a RAID-0 is more unlikely and will provide even less of a benefit for them.

Point being, RAID-0 is useless for most people, and chances are, if you will benefit from it, you'll know that anyway, say for example you're working with video streams or some such.

 

[Jiggz]

Originally posted by: JEDIYoda

Originally posted by: RebateMonger

Originally posted by: joshsquall
So the controller introduces no new threats to the drives. All I needed to know. Thanks.

Well, that's not completely true. First, many RAID0 arrays are built using built-in RAID chipsets, some of which aren't quite as reliable as high-end separate RAID controllers. RAID chipsets seem to be somewhat more prone to failure than "standard" IDE chipsets, which are pretty well developed and tested.

Second, ANY RAID array is more complex than a simple IDE interface, and people make mistakes managing their RAID arrays. I've never seen an estimate of this risk, but it's obvious that the human factor is there and causes array failures. A search through AnandTech's Forums will show many people losing their RAID data even though no drive failed.

I use raid 0 on 2 of my riggs and I will tell you that without a doubt 99% of all raid0 failures are due to human error.....

Both of mine were my fault not the systems fault...yet
Rule #1 to anybody using raid0 always back your important stuff to another harddrive!!

And Rule #1A, is if you are not using RAID 0, always back up your important stuff anyways!

So the moral of the story is: Always back up data, whether you use RAID 0 or single hdd! And since the price of hdd is affordable than ever, you might as well go with RAID 0, because you'll need to back up anyways!

 

[ch33zw1z]

Originally posted by: Cogman

Originally posted by: Riverhound777
If you want the "increase in speed" from RAID-0, use RAID-5. It isn't like hard drives are that expensive these days.

I second that motion, RAID 5 is a bit more unique then RAID-0 because the more Hard-Drives you have, the less likely a failure is going to take out your system.

that's crude description of RAID 5. it's not more unique, it's more reliable. RAID 0 and RAID 5 are much different. RAID 0 has NO reliability, with RAID 5 you can lose 1 drive and still be up and running in a "degraded" state...giving you *cross fingers* enough time to replace the failed drive. unless of course you have a hot spare, then it can fail over to the spare and do all the parity calculations right away...leaving you with less of a head ache.

 

[Slammy1]

With a good backup routine R0 really isn't that threatening. It would seem most of the problems I've seen/heard of with RAID0 are operator error or system instability. Definitely a higher risk than a single drive, I'd even go so far as to say simple probability arguments do not cover true failure rates (they're higher), but with well constructed drives and good backup habits failure shouldn't be your concern; instead figure if there really is a reason to run RAID0. The controller definitely does contribute to failure rates, I've seen controller failure before and I'm not the l33t build God of Knowledge/experience.

 

[Rubycon]

Originally posted by: ch33zw1z
that's crude description of RAID 5. it's not more unique, it's more reliable. RAID 0 and RAID 5 are much different. RAID 0 has NO reliability, with RAID 5 you can lose 1 drive and still be up and running in a "degraded" state...giving you *cross fingers* enough time to replace the failed drive. unless of course you have a hot spare, then it can fail over to the spare and do all the parity calculations right away...leaving you with less of a head ache.

RAID5 has an achilles heel however. If another disk goes when it's degraded, EVERYTHING is gone. With R5 arrays over 4 disks one should consider RAID6 instead as it can handle a failure of TWO disks. Even with a hotspare, large arrays can take many hours to rebuild. During that time you're vulnerable.

 

[ch33zw1z]

Originally posted by: Rubycon

Originally posted by: ch33zw1z
that's crude description of RAID 5. it's not more unique, it's more reliable. RAID 0 and RAID 5 are much different. RAID 0 has NO reliability, with RAID 5 you can lose 1 drive and still be up and running in a "degraded" state...giving you *cross fingers* enough time to replace the failed drive. unless of course you have a hot spare, then it can fail over to the spare and do all the parity calculations right away...leaving you with less of a head ache.

RAID5 has an achilles heel however. If another disk goes when it's degraded, EVERYTHING is gone. With R5 arrays over 4 disks one should consider RAID6 instead as it can handle a failure of TWO disks. Even with a hotspare, large arrays can take many hours to rebuild. During that time you're vulnerable.

Hopefully the OP will read all our stuff and realize there's more options than "RAID" 0.

 

[StrangerGuy]

Too much risk and effort involved in a RAID 0 array, especially for motherboard RAID, for the miniscule real-world speedup.

 

[amdskip]

I had a raid 0 setup for around 2 years and I never had a bit of trouble with it. I took it down to upgrade hard drives is all.

 

[corkyg]

I guess a lot of it has to do with your tolerance for the possibility of failure. I had a RAID 0 array years ago (before SATA was invented.) It was OK - but soon I found no advantages as hard drives became bigger and faster. There is some increase in the probablility of failure with multiple drives, but not to the extent of 1X per drive (my old array had 3 drives - all identical.) Each piece of hardware increases exposure.

 

[xtknight]

Failure_rate = 2(likelihood of one-disk failure) + (any_bugs_in_RAID_controller).

 

[Gunslinger08]

Originally posted by: ch33zw1z

Originally posted by: Rubycon

Originally posted by: ch33zw1z
that's crude description of RAID 5. it's not more unique, it's more reliable. RAID 0 and RAID 5 are much different. RAID 0 has NO reliability, with RAID 5 you can lose 1 drive and still be up and running in a "degraded" state...giving you *cross fingers* enough time to replace the failed drive. unless of course you have a hot spare, then it can fail over to the spare and do all the parity calculations right away...leaving you with less of a head ache.

RAID5 has an achilles heel however. If another disk goes when it's degraded, EVERYTHING is gone. With R5 arrays over 4 disks one should consider RAID6 instead as it can handle a failure of TWO disks. Even with a hotspare, large arrays can take many hours to rebuild. During that time you're vulnerable.

Hopefully the OP will read all our stuff and realize there's more options than "RAID" 0.

Oh, I know there are. I've setup RAID 5 and RAID 10 arrays for clients that demanded little/no downtime when drives fail. I just wanted to see people's real world experience with RAID 0 arrays.

 

[ch33zw1z]

Originally posted by: joshsquall

Originally posted by: ch33zw1z

Originally posted by: Rubycon

Originally posted by: ch33zw1z
that's crude description of RAID 5. it's not more unique, it's more reliable. RAID 0 and RAID 5 are much different. RAID 0 has NO reliability, with RAID 5 you can lose 1 drive and still be up and running in a "degraded" state...giving you *cross fingers* enough time to replace the failed drive. unless of course you have a hot spare, then it can fail over to the spare and do all the parity calculations right away...leaving you with less of a head ache.

RAID5 has an achilles heel however. If another disk goes when it's degraded, EVERYTHING is gone. With R5 arrays over 4 disks one should consider RAID6 instead as it can handle a failure of TWO disks. Even with a hotspare, large arrays can take many hours to rebuild. During that time you're vulnerable.

Hopefully the OP will read all our stuff and realize there's more options than "RAID" 0.

Oh, I know there are. I've setup RAID 5 and RAID 10 arrays for clients that demanded little/no downtime when drives fail. I just wanted to see people's real world experience with RAID 0 arrays.

My personal, at home, real world exp: 2x36GB raptor RAID 0 array sh!t the bed after two months when 1 brand new drive failed. I said fvck that, created my install on one 74GB and made a image from the fresh install onto the still working 36GB. My only try w/ RAID 0, I am currently running a RAID 1 w/ 2x250GB WD KS drives.

I have yet to see another RAID 0, the arrays I typically see are 1's, or 5+'s.

 

[RebateMonger]

This is an interesting article: Why RAID is (usually) a Terrible Idea. Although the RAID failure rate is anectodal, there are some interesting numbers on the failure rates of single drives versus RAID arrays.

The author (who runs a mid-size PC supplier), shows failure rates of single hard drives in the range of 1.5 to 3.2% in the first year.

But here's what he says about RAID arrays deployed by his company:

"Unfortunately, it is not as clear of a number when it comes down to how many RAID failures there have been. Since it is not a black and white failure issue, I do not have hard data. However, at the agreement of our support staff, I estimate that anywhere from 25% to 30% of our customers with RAID will call us at some point in the first year to report a degraded RAID array or problem directly resulting from their RAID configuration. Granted, a failed RAID1 array does not mean data loss, but it certainly means a long, frustrating hassle. On the other hand, a single hard drive will often give warning signs before failure, so that scenario doesn't necessarily mean data loss either."

 

[Blain]

Originally posted by: joshsquall
How often does RAID 0 really fail?

2.36% - 4.71%

 

[Cold Canuck]

I undoubtedly misunderstand how raid arrays work, but in RAID 0, isn't only half the data written to each drive, thereby speeding up the read/write speeds?
Wouldn't that result in less movement and wear on the actuator and associated parts, not more?

 

[corkyg]

Holy necro! This is a 9 year old thread. With SSDs, the big advantage of RAID 0 sort of goes away. Forget wear and tear - just think of recoverability. With RAID 0 it is very difficult if not beyond the ken of the average user. I see it more of a geek fad than a real advantage.

 

[dave_the_nerd]

A RAID 0 is twice as likely to fail as a single HDD.

How much that bothers you is generally a function of how many HDDs you've had fail over the years.

 

[dave_the_nerd]

I undoubtedly misunderstand how raid arrays work, but in RAID 0, isn't only half the data written to each drive, thereby speeding up the read/write speeds?
Wouldn't that result in less movement and wear on the actuator and associated parts, not more?

Sure, but that's not the only factor in drive failure.

 

[dave_the_nerd]

Holy necro! This is a 9 year old thread. With SSDs, the big advantage of RAID 0 sort of goes away. Forget wear and tear - just think of recoverability. With RAID 0 it is very difficult if not beyond the ken of the average user. I see it more of a geek fad than a real advantage.

But hand-wringing about absurd theoreticals to show that one technology is somehow superior to another is always topical!

 

[Cold Canuck]

Unfortunately, mechanical drives in any number of configurations will be with us for some years to come, at least until the cost of SSDs comes down to a level similar to those same mechanical drives.
I've only ever once used a RAID 0 array (quite some years ago) and like you, feel that using a RAID 0 array just doesn't provide enough benefit to warrant putting your data at risk...it just doesn't make sense.
Sorry for dredging up such an old thread.

 

[Cold Canuck]

BTW...thanks for such speedy replies.
Cheers, eh.