Raid 0 system

busheadfox · Post by **busheadfox** » Thu Mar 06, 2003 12:00 am

Would it be a bad idea to use 2 100gig hard drives in a raid 0 system as opposed to just 1 larger drive in a single drive system. I like the idea of a very fast hard drive system but I do understand that 2 drives have twice the amount of problems as a single drive does. It will be used mostly for video editing and movie making which makes a fast drive system very nice to have.

Or do you think a better way would be to have a 100 gig for windows and programs and a pair of 100 gigs for a raid 0 setup to be used only for the video and graphic stuff.

Post by **FlyingPenguin** » Thu Mar 06, 2003 7:02 am

I played around with RAID striping for a year and in my opinion it's not worth it. As you mentioned there's the increased risk of loss of data due to drive failure.

Performace is NOT going to be as spectacular as you may have been led to believe.

Frankly, with the speed and amount of cache in modern ATA133 drives it's just not worth it.

Invisible Evil · Post by **Invisible Evil** » Thu Mar 06, 2003 12:44 pm

Yeah I tried it and really didnt think It was worth it @ the risk you run, I was using a couple of 40 GB drive, and I was just like hell get a 80 ya know.

Hipnotic_Tranz · Post by **Hipnotic_Tranz** » Fri Mar 07, 2003 10:00 am

I dunno, every one makes it sound like if you run RAID-0 then you're throwing your data away. Ok, yes the probablility of one of the two drives failing is higher than a single drive, but that probability alone isn't very high. Atleast, I've never had a hard drive suddenly die out of nowhere on me. There have atleast been signs. People make it out to seem like when you stripe the drives the physical drive becomes less reliable and I just don't believe that is true.

Back to the point. Is it worth it? From what people have been saying lately, no. As long as you have a nice drive. Nice as in, those WD 8meg cache drives, they'll give you just as good of performance as a RAID-0 array. And since you're doing video editing, you'd want that speed, so don't cheap out and get some POS drive.

Good luck.

Busby · Post by **Busby** » Fri Mar 07, 2003 12:26 pm

But when you get the 8MB cache drives in a RAID0 array, you get awesome preformance. I've used single drive systems, regular drives in a RAID0 array and the new 8MB drives in a RAID0 array. I can tell a difference between them. It just seems a little snappier. Benchmarks are good too. I've used 3 different drive types in RAID arrays (Maxtor, and WD). All have never failed on me. I just changed the drives around from WD to Maxtor 2MB because of ATA133 speeds and the silence of the drives and went from Maxtor 60GB to 80GB with 8MB cache.

SsZERO · Post by **SsZERO** » Sat Mar 08, 2003 2:28 am

WIth a single drive or raid-0, drive failure is not an issue -- because either way you lose all or most of your data. Only one drive needs to fail to mess things up in both cases, therefore the risk level is the same for both situations. There is no fault tolerance in a single drive system, or a raid-0 config.

If you are just using Raid-0 with two IDE drives, and your OS happens to be windows XP, you can use the 'dynamic drive' feature. This feature will allow you to have a software based raid array which will outperform most of the raid controllers that are built into MBs, such as promise and highpoint. If you want a high performance IDE Raid controller, you will want something by 3ware. The Promise and Highpoint integrated controllers are basically standard IDE controllers with raid software in their bios -- they do not actually process data as a hardware raid unit would.

As far as being a worthwhile upgrade...raid arrays will improve load times for games and applications, however "snappiness" is a product of HD seek time, so if you want a snappier system, you'll want a drive with low seeks.

DocSilly · Post by **DocSilly** » Sat Mar 08, 2003 7:54 am

SsZERO

I can not fully agree .... it is true that you lose your data when a HDD fails in either single-setup or RAID-0 ... BUT ... when you use more drives for one volume then you have a higher risk of a drive failure (the more HDDs, the sooner one will fail).

Lets compare two single drives vs one RAID-0 with two drives.

Single setup, OS on HDD1, videos on HDD2:
- HDD1 dies = you lose your OS, videos remain
- HDD2 dies = you lose your videos, OS remains

RAID-0 setup, OS and video on HDD1/2 stripeset:
- HDD1 dies = all is lost
- HDD2 dies = all is lost

Using RAID-0 doesn't mean your data will definetly be lost sooner, it's only that the risk is higher. I recently lost a single 40GB HDD without warning, it wasn't detected by the BIOS after a clean shutdown.

Again, RAID 0 does have its advantages in a handful of key applications and uses where data files are huge and/or data requests are highly sequential in nature. Data requests are not highly sequential, however, in typical desktop productivity and gaming usage patterns, the most often cited in "Help me build my RAID 0!" posts.

This is from Storagereviews frontpage where they compared single drive vs RAID-0

busheadfox

Video-editing is one of the few tasks where you can take advantage of RAID-0 though it ain't really necessary with todays fast IDE drives. You can use your 2x100GB drives in a RAID-0 setup for editing but I would use a (small) single HDD for your OS/programs.

Post by **FlyingPenguin** » Sat Mar 08, 2003 8:18 am

I've never had a hard drive suddenly die out of nowhere on me

You're lucky Hip. I've seen PLENTY of drives fail without warning. Modern drives rarely give you warning like old drives used to.

Used to be you'd start getting some bad sectors and that gave you plenty of notice. Due to the design of modern drives, however, usually all you hear is a clunk and it's dead

Hipnotic_Tranz · Post by **Hipnotic_Tranz** » Sat Mar 08, 2003 10:36 am

I agree with SsZERO. Most people who are wondering whether to go with RAID-0 or not are either looking at getting one large drive or two smaller and putting them in RAID and like he said, either way if one fails you're screwed so it doesn't really matter.

So now it's just a point of whether you want to spend the money on a controller (unless it's already integrated on your motherboard). From the benches of the latest hard drives it's not worth the money of buying a controller (if you have to). I'm running RAID now because at the time it was cheaper for me to get the two 40gig drives and since my motherboard already had a high-point controller then I figured theres no reason not to

SsZERO · Post by **SsZERO** » Sat Mar 08, 2003 4:04 pm

Assuming two identical hard drives with identical MTBF, both drives have exactly the same chance of failing. It's not a linear equation, since only one drive needs to fail in both cases. Having two drives does not increase the likelyhood of having one drive fail, since both drives have the same MTBF and are in the same environment, the failure probability is equal to one of the drives in the array.

Example:
Base on what you are saying:
- Config 1 Single HD - Failure Probability: 50/50
- Config 2 Dual HD Raid 0 - Failure Probability: 100/100.......Because you are combining the failure probability of two drives -- which is not how it works.

Based on what I am saying:
- Config 2 Dual HD Raid 0 - Failure Probability: 50/50 per drive = 50/50 per array

And we are not talking about 2 drives seperately -- we are talking about ONE drive all by itself, or TWO drives in a RAID-0 config. Obviously, if you have multiple drives operating individually, you have a basic level of fault tolerance.

Originally posted by DocSilly
SsZERO

I can not fully agree .... it is true that you lose your data when a HDD fails in either single-setup or RAID-0 ... BUT ... when you use more drives for one volume then you have a higher risk of a drive failure (the more HDDs, the sooner one will fail).

Lets compare two single drives vs one RAID-0 with two drives.

Single setup, OS on HDD1, videos on HDD2:
- HDD1 dies = you lose your OS, videos remain
- HDD2 dies = you lose your videos, OS remains

RAID-0 setup, OS and video on HDD1/2 stripeset:
- HDD1 dies = all is lost
- HDD2 dies = all is lost

Using RAID-0 doesn't mean your data will definetly be lost sooner, it's only that the risk is higher. I recently lost a single 40GB HDD without warning, it wasn't detected by the BIOS after a clean shutdown.

busheadfox

Video-editing is one of the few tasks where you can take advantage of RAID-0 though it ain't really necessary with todays fast IDE drives. You can use your 2x100GB drives in a RAID-0 setup for editing but I would use a (small) single HDD for your OS/programs.

SsZERO · Post by **SsZERO** » Sat Mar 08, 2003 4:09 pm

Actually, if you use WinXP, you don't need a raid controller...just two available IDE channels for Raid 0.

Check out: Control Panel > Administrative Tools > Disk Management

A dynamic disk will be faster than low end Raid controllers (like the ones built into motherboards), but you will not be able to access the data with another OS like Linux, even if the OS supports NTFS.

Originally posted by Hipnotic_Tranz
I agree with SsZERO. Most people who are wondering whether to go with RAID-0 or not are either looking at getting one large drive or two smaller and putting them in RAID and like he said, either way if one fails you're screwed so it doesn't really matter.

So now it's just a point of whether you want to spend the money on a controller (unless it's already integrated on your motherboard). From the benches of the latest hard drives it's not worth the money of buying a controller (if you have to). I'm running RAID now because at the time it was cheaper for me to get the two 40gig drives and since my motherboard already had a high-point controller then I figured theres no reason not to

Busby · Post by **Busby** » Sat Mar 08, 2003 6:11 pm

SsZERO: Do you have benchmarks to backup the Dynamic Disk vs. RAID controller battle? I find that very hard to believe myself, but it could be true.

SsZERO · Post by **SsZERO** » Sat Mar 08, 2003 10:09 pm

I don't have any pics of my own benchmarks, but if you check out storagereview or 2cpu forums, you'll find that quite a few people have discovered the same thing. Do a search on the topic of "ide raid" or something along those lines.

The raid controller integrated into most motherboards does not provide any type of processing -- it is merely a standard IDE controller with raid config software in its firmware. What it boils down to is you have a full software raid either way -- so using window's XP version works better for raid 0 with IDE drives. Typically, a hardware based raid controller will have at least some onboard cache which is used for processing the data. No cache generally indicates that you are using a glorified IDE card.

But like I said, if you get a real controller like the 3ware Escalade, you would get better performance with the controller, because it is an actual raid controller. You can also use higher stripe sizes to yield improved peak transfer rates, since these controllers can accomodate up to 256MB of cache.