Is Raid 0 worth the loss in space?

Dougx1317

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I currently have a Seagate 320GB hard drive in my computer, but I need more storage. I really wanted to try RAID 0, but 320GB drives cost about the same as 500GB. Is RAID 0 worth buying the smaller drive?

Also, why do 1TB drives cost the same as two 500GB drives? I'd think they'd be priced differently.

System: AMD X2 6000+, Asus Crosshair, 2GB 800 RAM, 9800GT
 
1TB drives platters have a higher density plus they don't have to worry about the extra moters, read/write heads and housing that would be in 2 500GB drives.

What do you do with your system? for most people raid 0 isn't worth the hassle period.
 

mlcloud

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If you have a high-end quad core build, then I'd say the raid 0 is very well worth it. Storage has long been the bottleneck of many systems, but now it's actually significant with the advent of highly-overclockable quads.

However, if you're running a duo core/gaming build and don't care much about a few seconds of loading/boot time or a faster encode/unzip/RARing... then no, there's no reason for raid 0.
 

Dougx1317

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Right now I have a X2 6000+, but I'm going upgrade to a quad pretty soon. If I were wanting 1TB of storage wouldn't two 500GB drives be better so I would at least have the option for RAID 0? Would you guys recommend getting a single one 1TB drive for any reason?

Also, is RAID 0 really that much of a hassle to set up? I wouldn't need to buy any other hardware to run RAID 0 would I? I assumed it would only take a few changes in the bios. Is it more than that?
 

mlcloud

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Dougx1317, for each hard drive you have, you add to the probability of a hard drive failing.

Now imagine if all the hard drives were connected somehow, and so if one died, all the others would die. In otherwords, 2 500gb's in RAID 0 have twice the chance of failing (and thus, theoretically half the lifetime) of a 1TB drive in exchange for improved read/write speeds.

And whether RAID 0 is a hassle or not depends on which motherboard you have. And good RAID controllers are expensive.
 

Dougx1317

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Mlcloud, are you recommending I just buy a single 1TB drive? I've never had a hard drive fail before. Is it really that likely? I know RAID would double the chance of failure but wouldn't it still be a low chance?

Also, do I have to buy a separate RAID controller? I have an Asus Crosshair now and was planning on getting a ~$120 Asus board when I upgrade.
 

mlcloud

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I wasn't recommending anything - I'm honestly not an expert on these parts, but people do use RAIDs regularly and the returns are definitely worth it (I know I'm going to read up more on it once I purchase another harddrive; my single 640gb WD Caviar Black is the biggest bottleneck in my system), especially if you have backups that can restore the data onto the drives.

And yeah, the failure rate is probably pretty damn low. But I'm just making sure we're not missing out on any facts here. The recommendation someone with more knowledge will have to make.
 

Dougx1317

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Thanks for all the help. From what I've been reading, there doesn't seem to be any real negatives to using RAID 0. But it also sounds like I won't see much of a difference.

I curious so I'll probably try it out. If anyone else has any information or advice, I'd love to hear it.
 
RAID 0 only helps with situation where you need faster sequential reads and writes. I believe those are audio/video recording and recoding. Games use (i believe) more random read and writes. So while it will load the lvls faster you won't see a noticeable improvement in fps. RAID 0 is not really RAID as it doesn't offer any redundancy. (defined as the ability to keep the system up and running after a drive failure) In fact it multiplies the chances for failure by the number of drives. This is why most people would recomend a RAID0 for the OS and a stand alone drive for storage.

For multi tasking RAID 1 is a better option as it off split seeks. Since both drives have the same data each one can search for a different item. It also adds redundancy

 

Dougx1317

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It doesn't sound like RAID 0 would be good for what I do, and I don't have precious enough data for RAID 1.

If I were to not use RAID of any type, would there be any advantage/disadvantage for two 500GB or a single 1TB drive?

Would a 640GB be better than a 500GB hard drive?
 
Because of the greater data density 1TB drives are typically faster then 500GB drives. I would suggest getting a 1TB drive and making a partition for OS, programs, page file and another partition for storage.

Some people say that with 2 drives you can put the OS on one, programs in another and split the page file between both. I don't feel it's worth the hassle of having to juggle your storage between the two drives. But again I've never used this setup.

a 640GB drive in most cases is better then a 500GB drive because of greater data density.

 

duxducis

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tested those 2x500gb drives
no raid maxx read speed 120mb/s
Raid 1 100-120mb/s (slight loss)
Raid 0 160-190mb/s

I have used Raid 0 for long time and liked it as long as you back up important data. (so basicly need 3 HD's 2 for raid and 1 for back up)
I would only recommend Raid 1, to users with super beginner computer skills, if u can manage files 2 separate HD"s will be much better

Right now i have 2x640gb drives (got those for $5 more then 500gb version) and partitioned them like so..

30-66-500gb (system-backup-other), and 30-200-66-300 for second drive (system-games-backup-other)
after installing vista i clone my system partition to second drive and later sync it with software like once a day or week.
200gb partition is for games only, 66gb partition is for important data i like to keep on my computer and it is set up to auto sync up with the others drive 66gb partition.
With this setup my data is safe, i always have back up windows, and loose 100gb of storage for redundancy instead of whole second drive.

thou more expensive then 1 drive, having 2 drives is very beneficial (installing something or copying, running games from iso, using virtual pc, pretty much any HD intensive task on 1 drive is super slow, compared if you install from second drive) drive to drive speeds are very fast, partition to partition on same drive is to slow for me.

 
Extract from below link
Quote is for 2 500 Gig or larger HD's in raid0

"With the larger HDD you can use "short stroking" which will cut your access time down to 8.5 -> 9.5 mSec. A 200 Gig Short stroke will limit your operating system to the outer 15 -> 20 % of the platters. The higher density (on the -12 500 Gigs per platter) will offset some off the diff in RPMs "

http://www.tomshardware.com/forum/forum2.php?config=tomshardwareus.inc&cat=32&post=250125&page=1&p=1&sondage=0&owntopic=1&trash=0&trash_post=0&print=0&numreponse=0&quote_only=0&new=0&nojs=0

A 2nd discussion on Raid0 worth looking at

http://www.tomshardware.com/forum/forum2.php?config=tomshardwareus.inc&cat=32&post=249993&page=1&p=1&sondage=0&owntopic=1&trash=0&trash_post=0&print=0&numreponse=0&quote_only=0&new=0&nojs=0
 

Dougx1317

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Because of the greater data density 1TB drives are typically faster then 500GB drives.
So, the larger the capacity, the faster the drive is? I would have expected larger drives to be slower. Does that mean that 1.5TB drives are even faster?

tested those 2x500gb drives
no raid maxx read speed 120mb/s
Raid 1 100-120mb/s (slight loss)
Raid 0 160-190mb/s
These readouts make RAID 0 look very appealing. But do you agree with the rest of the suggestions that RAID 0 wouldn't help me unless I moved large files constantly. Would I be able to take advantage of this speed increase in OS loading, games, or normal tasks?

loose 100gb of storage for redundancy instead of whole second drive.
This sounds like a good compromise. I'll consider something like this.

I looked into short stroking, but I thought that you lost some storage space with this method. If not, what are the downsides to short stroking, and how would I set it up? Would it be better with one or two drives?
 
yes because the disk remain the same size, the data has to be pushed closer together. since the data is closer together the head doesn't have to travel as far. Most modern 1TB drives (samsung spinpoint f1) will outperform the older 10k WD raptors.

I never understood what makes short stroking different then simply creating a parition. I use paritions with my 2 WD velociraptors to keep my data on the outer edges. (in theory anyway)
 
PsyKhigZero
Just a Quess. With Partitioning The drive is still treated as one drive and Data is limited to designated sectors. With Raid0 the two drives are joined together into one drive and then with Short Stroking they are treated as two drives. The raid0 effectively doubles the outer 15 -> 20% of disk space (Short stroke, or partitioning) for operating system/progams.

dougx1317
Short stroking is done very simular to partioning, When creating the array you just tell it you only want to create the 1st array as xxx (ie 200 Gigs). Select/change default strip size to a smaller value ie 32K (my bios 64K was smallest). This increases the number of files that will share drives.
Then select remainder of drive for 2nd Array using defaults.

You do not lose space in short stroking unless you choose to. As to benifits of short stroking, I have not done enough testing to verify that it really helps over just partitioning. It definitly improved access time under bench mark. (See the two links I posted above.)
 

jrst

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You can also nominally double the amount of space in the fast/outer zone with a drive that's twice as large (not quite the same, but I'd be surprised if you could tell the difference unless you have very large partitions).

Partitioning is as effective as firmware-based short-stroking, unless the drive firmware has has some very peculiar properties. The objective is to reduce the distance the heads must travel to access a given amount of information. In general, the drive's not going to wander over the rest of the disk unless told to (unless, e.g., the controller or drive firmware is set for patrol-read, but even that is likely to be noise in most cases).

Decreasing the stripe size so more files are split across disks is of dubious benefit, and likely counter-productive. In most cases, you've simply slowed down the completion of the IO until all disks complete seek+xfer.

E.g., given a single reasonably fast drive with a 7ms average seek time, an average xfer rate of 50MBs, and an xfer size of 64KB, the total IO time = 7ms (seek) + 1.28ms (xfer) = 8.28ms. If you split that across two drives, and if the two drives are not with 0.64ms seek time of each other, you lose--that is, if the second drive doesn't complete its seek and start its xfer within 0.64ms of when the first drive started its xfer. Decreasing the stripe size and increasing the number of drives can exacerbate the situation.

Ensuring drives obtain that level of coordination is difficult, and comes with a price (and not what you're going to see with typical mobo RAID). Which is why larger stripe sizes are generally preferred--unless you have a very random IO pattern*--as seek time is orders of magnitude greater than xfer time for typical IOs.


* Edit: and the size of the IO is typically the same as the stripe size, so you really do get the effective benefit of multiple independent heads/IOs.
 

michiganlaw

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I have an Abit p35 Pro motherboard, Intel QX6600, running at 3.1 GHZ with Thermaltake Water Cooling cpu to 52 degrees C running Raid 0 on two Hitachi 80MB drives. This setup has been running for 2 years without a drive failure. However, it took me a while to get the cpu running stabily at that speed. I run Acronis True Image Home for backup for safety. I tested my drives on an old program called HDTach which rated my Raid 0 array equal to a scsi Ultra 320.

There is no trouble setting up Raid 0. Almost any MB that supports it has a bios utility to set it up in less than 10 minutes. My system flies, and I don't wait for anything to happen (except internet delays).

Herb
lawmichigan@gmail.com
 
Western Digital 2TB Black:

This drive has just been released and benchmarked. It's top-end average Read rate goes over 150MB/second (rated at 138MB/sec but benchmarks were higher). It's truly amazing and would be recommended for someone like me who wants it for a high performance MAIN drive when you have LOTS of games (just install all my games and don't keep uninstalling/reinstalling for space).

Sure it costs a little more and is noisier than some drives but factor in having one drive instead of two and not bothering with RAID0.

There are pros and cons when comparing it to a Velociraptor but if I had to choose I'd get the 2TB Black WD. If I only needed the 300GB space for my main drive as most would I'd recommend going that way with a second 1TB GREEN WD drive (and backup Windows etc.)

The 2TB Black is FASTER for average reads. In fact, when you consider hard drives drop off to about 50% of the speed on the inner platter (the last to be written to) that's even more impressive. The Velociraptor drops to about 60MB/second when full but at the 300GB point on the 2TB Black it hasn't dropped much so it's likely above 140MB/second!

The Black should be a little noisier. It takes a little longer to spin up (not something I care too much about in a desktop).

I thought the Velociraptor would have faster seek times but apparently they are the same at 4.2ms. I guess the high density and 3.5" size offsets the Velociraptors 2.5" and higher RPM (10000RPM).

Summary:
The 2TB Black is a serious consideration for those who want high speed Windows and Gaming loading times. It has advantages over RAID0. I would partition it but still use a 1TB GREEN drive for backing up an Image of Windows and other data. Using eSATA for the second drive is a great choice so you can turn it OFF when not needed.
(note for SATA->poweredSATA/eSATA you can find the drive without rebooting by entering the Device Manager and scan for new hardware)