RAID 0 worthless?

[Machine350]

What do you guys make of this article? There are so many people doing raid 0 setups, but if this article is right, whats the point?

null

 

[chocoruacal]

I have only RAIDed ATA drives (40 gb - 200 gb drives). That said, I have NEVER seen any noticeable increase in speed doing so. Maybe i'm just too insensitive, maybe the RAID controllers/drives I used sucked. Seemed to me though to be in the same club as low latency RAM...good for benchmarks, bad for wallet. But then, I'm sure lots of people will chime in and say how their Windows loads in 2 seconds and they gained 50 FPS in Quake by doing so, so YMMV :laugh:

 

[SaturnX]

The only application I've ever seen any noticeable increase in performance is when manipulating extremely large files, such is the case with intensive video editing/processing, and/or 3d animation. Essientially anything that's the extemely data intensive will benefit from a RAID-0 array. For the average PC user, it's nothing but "braging rights" and unless you're actually making use of it, no, there isn't much point.

--Mark

 

[Machine350]

To me it doesn't make sense. You have to buy another drive and a controller card (if your mobo doesn't already have it) and you risk losing all your data if one of the two drives fail. All for a theoretical speed increase of what? Maybe someone can help me with this?

 

[Matthias99]

Originally posted by: Machine350
To me it doesn't make sense. You have to buy another drive and a controller card (if your mobo doesn't already have it) and you risk losing all your data if one of the two drives fail. All for a theoretical speed increase of what? Maybe someone can help me with this?

Well, for some applications (like video editing), the speed increase can be significant (essentially, it halves the time required to load and save extremely large files). Also, some applications can only work on a single drive/folder (or are easier to work with in such a configuration), so it can be useful to have 400+GB of space in a single partition. In terms of security -- yes, your RAID0 has double the risk of failing of a single drive. However, if you store your data on two separate 200GB disks, you have the same chance of *one* of those disks failing. If you have 400GB of data, and losing any of it is unacceptable, you're not any worse off with a RAID0 than with two separate 200GB disks.

That said, for typical desktop configurations, RAID0 is probably not worth the hassle (nor the expense if you don't have on board RAID).

 

[SaturnX]

Yes, there is the added risk of losing data, since if you lose one of 2 drives in a RAID-0 setup, yeah all your data is toast, but like I mentioned, when you're shifting around large files and reading/writing large amounts to the drives, by "striping" it across 2 or more drives, the performance increases.

Another analogy would be; why its recommended to have your windows pagefile, or *nix swap partition, on a seperate PHYSICAL drive, rather than partition or the same drive that you've got your OS install on, since there's unobstructed access to the drive. The same principal applies with RAID-0 and large file manipulation, writing the odds/evens to seperate drives reduces the individual load to one drive.

--Mark

 

[imported_Nacelle]

Divx encoding and editing on RAID-0 is the shiznits.

 

[diablonhn]

tweakerz.net did a great counter argument, proving without a doubt that RAID 0 improves speed for many people in many cases

people influenced by storagereview and anandtech would bring up irrational arguments like cases used by tweakerz were not typical of desktop users - I didn't know copying files and multitasking were not in the domain of desktop users??!?!

one of the main problems with desktops is hard drive thrashing in which no useful work is done and it takes 5x,10x,100x longer to finish an I/O job (similar to process switching on the operating system side). With today's single drive systems and physical perfomance limits of hard drives, hard drive thrashing is a very real reality. It is easy to thrash a hard drive - copying a large file to the same hard drive in win98 is enough.

RAID 0 prevents thrashing by giving the computer extra breathing room. MANY non-power, non- CS/CE/EE/Math/Physics/Psych desktop users have two dozen or more processes running, many unnecessary, some malware, an outdated AV, and maybe a virus or two. The OS is constantly context switching, paging, and caching to the hard drive to make good use of memory but with the overhead the system is slowed to a crawl. The user can improve speed by adding more memory or by using RAID. By adding memory, less stuff needs to be driven out of cache. With RAID 0, caching out is faster, as well as several other improvements. Thus RAID 0 not only helps power desktop users, but also grandmas and posers out there.

For people with 256MB of 1066 RAMBUS memory or less from the Dell deal, updating the memory is NOT an option. Therefore the only option is RAID 0.


RELIABILITY
---------------
As far as reliability is concerned, RAID 0 will actually improve the lifespan of the individual RAIDed hard drives verus single drives.

Manufacturers list MTBF, MTTF of a device but have you ever wondered how did they come up with those numbers? It is an inexact science with a lot of exaggeration and no standards. My professor at UCSD, a visiting researcher to IBM storage labs, did not even know.

I fear that some manufacturers test the mean time before failure by letting the hard drives run idle. Measuring the MTBF of an idle device is very misleading. Many things in the real world have their MTBF stated with respect to workload. For example, a relay switch life is measured in how many switches before the realy dies. Because a relay is always on/idle in one state, its idle MTBF can easily be 100,000 hours, or as high as 1,000,000 hours when not switching. But when switching, it's MTBF can be as low as a day.

With RAID 0, the workload on the hard drives is reduced because the I/O jobs are finished faster with less thrashing. Less work in ANY setting and in ANY industry translates to longer life.


CONCLUSION
----------------

In conclusion, RAID 0 is FOR desktop users. The simple Markov models that people reherse so often do not do an adequate job of predicting the MTBF of RAIDed systems. The MTBF should be measured in gigabytes transfered from the beginning of the platter to the edge before failure or bad sector encounterd multiplied by the mean time for each transfered gigabyte in non-server environments.

 

[Machine350]

Lets say you had a WD raptor drive, 512 mb ram, and ~$150 to upgrade. What would be the better upgrade, to add another raptor drive in a raid 0 setup or to add another 512 mb of ram?

 

[nageov3t]

I wouldn't say that it's worthless, but IMO, it's definitely not worth the added risk of total data loss.

 

[Glavinsolo]

I wouldn't have my setup any other way. I put one of my 74 raptors alone and I can't stand how slow it is installing things and transfering media.

2 of these bad boys in a raid 0? It is absolutely amazing. If I were to show you I would. I mount all my images on a virtual drive and the install time is second to none. As far as boot times (no it is actually longer) But when you have many files that need to be transfered or are constantly encoding these drives shave off a lot of time.

Summary:
If you work on your computer as if it is a server = YES get a RAID 0 setup
If not and you are just a single user = NO get a RAID 1 if you must spend money

If you are looking for a single drive check out

http://storagereview.com/php/benchmark/bench_sort.php

74gb raptor = 72mb/s transfer 2x74gb raptors raid0 = 126mb/s transfer

 

[Glavinsolo]

Originally posted by: Machine350
Lets say you had a WD raptor drive, 512 mb ram, and ~$150 to upgrade. What would be the better upgrade, to add another raptor drive in a raid 0 setup or to add another 512 mb of ram?

RAM

 

[dullard]

Look at the article more closely, almost 100% of the people who read it (and posted here) misinterpreted it. The article is comparing one faster drive to two slower drives in RAID 0. In that case, the article is correct that the one faster drive is the better purchase. The article didn't make any other conclusions - but the people reading the article did.

There have been many posters claiming that it is proof that RAID 0 is worthless. But go back and read the numbers more closely. Look at the single 36 GB Raptor vs the RAID 0 36 GB Raptors. Ignore the 73 GB Raptor as it has nothing to do with this topic.

Benchmark / RAID 0 36 GB Raptors / single 36 GB Raptor / Speed boost using RAID 0
UT2004 level loading / 29.4 / 34.1 / 13.8% faster with RAID 0
Far Cry level loading / 40.6 / 41.1 / 1.2% faster with RAID 0
Sysmark overall / 211 / 204 / 3.4% faster with RAID 0
Sysmark overall internet / 235 / 230 / 2.2% faster with RAID 0
Sysmark overall office / 189 / 180 / 5.0% faster with RAID 0
Sysmark communciation office / 196 / 171 / 14.7% faster with RAID 0

I got tired typing, but you can see the pattern. RAID 0 with two 36 GB drives is faster in every case than the single 36 GB drive. So looking at those numbers, do you still conclude that RAID 0 is worthless?

 

[Sunner]

Originally posted by: Glavinsolo
I wouldn't have my setup any other way. I put one of my 74 raptors alone and I can't stand how slow it is installing things and transfering media.

2 of these bad boys in a raid 0? It is absolutely amazing. If I were to show you I would. I mount all my images on a virtual drive and the install time is second to none. As far as boot times (no it is actually longer) But when you have many files that need to be transfered or are constantly encoding these drives shave off a lot of time.

Summary:
If you work on your computer as if it is a server = YES get a RAID 0 setup
If not and you are just a single user = NO get a RAID 1 if you must spend money

If you are looking for a single drive check out

http://storagereview.com/php/benchmark/bench_sort.php

74gb raptor = 72mb/s transfer 2x74gb raptors raid0 = 126mb/s transfer

The vast majority of users won't use a computer in a manner similar to a server, and the people who do will most likely know it and have some idea about what they can do to improve their situation.

IMO RAID-0 is like SMP, if you have to ask, you don't need it.

 

[jose]

Quote:

"IMO RAID-0 is like SMP, if you have to ask, you don't need it. "

Exactly !! I use it only for video editing, because 75g scsi drives cost $600 each. I get 140+ gigs for ~ $340 w/ the speed I want..

Regards,
Jose

 

[iwantanewcomputer]

moving and opening big files you will see a difference. it won't give extra fps but most of the little hiccups or freezes a system has are because of waiting on the hard drives. i think you would notice 1 wd raptor more than 2 7200rpms in raid0, but 99% of people who have 2 wd raptors in raid0 love them

 

[gsellis]

Originally posted by: SunnerIMO RAID-0 is like SMP, if you have to ask, you don't need it.

You know Sunner, I may have to use that as an attributed quote signature...

 

[Sunner]

Originally posted by: gsellis

Originally posted by: SunnerIMO RAID-0 is like SMP, if you have to ask, you don't need it.

You know Sunner, I may have to use that as an attributed quote signature...

Yay, my first sig material

:beer:

 

[addragyn]

Originally posted by: iwantanewcomputer
it won't give extra fps but most of the little hiccups or freezes a system has are because of waiting on the hard drives. i think you would notice 1 wd raptor more than 2 7200rpms in raid0, but 99% of people who have 2 wd raptors in raid0 love them

No, RAID 0 does NOT lower latency.

 

[beatle]

It also depends on what you call "video editing" and what software you use to do it. I edit commercials out of programs with Virtualdub (not a great NLE, but I can get it to work somewhat) and disk speed has almost no effect on using Virtualdub.

Converting your DVDs to divx, xvid, etc. doesn't qualify as video editing either, so in that sense, RAID 0 is a waste. I doubt I'll ever use it again.

 

[leeland]

interesting thread, bookmarked for later reading

 

[chocoruacal]

Originally posted by: Nacelle
Divx encoding and editing on RAID-0 is the shiznits.

What kind of CPU are you using that a single drive would be the limiting factor for speed? 50 ghz Xvid/MPEG2 encoding has always been fastest for me when working with two independent drives as opposed to a RAID 0.

 

[TerryMathews]

Originally posted by: addragyn

Originally posted by: iwantanewcomputer
it won't give extra fps but most of the little hiccups or freezes a system has are because of waiting on the hard drives. i think you would notice 1 wd raptor more than 2 7200rpms in raid0, but 99% of people who have 2 wd raptors in raid0 love them

No, RAID 0 does NOT lower latency.

Well... RAID 0 would double the effective cache size of the HDs in question due to the striping. IE if you stripe a pair of 8MB cache drives, you effectively have a single logical drive with a 16MB cache.

If the data you needed to burst transfer off the drives was 8MB < x < 16MB, then yes this would reduce hiccuping.

RAID is for work, not play.

 

[Markfw]

Raid 0 in SCSI is another matter. First, I have a DLT tape backup, and I regularly burn DVD's of my pictures, so failure of a driver is not a concern of mine, but for many people, it IS a big deal. Second, with 5 drives in raid0 I get insane seek times and transfer rates, but part of that is due to my caching controller with 128 meg of ram.

I have done raid0 on IDE before and it seemed a little faster, and proved out in nearly identical systems faster loading a game leve (multiplayer), so I wouldn;t say it is worthless, but I have since decided its not worth it for the small increase in speed.

 

[imported_Nacelle]

Originally posted by: beatle
It also depends on what you call "video editing" and what software you use to do it. I edit commercials out of programs with Virtualdub (not a great NLE, but I can get it to work somewhat) and disk speed has almost no effect on using Virtualdub.

Converting your DVDs to divx, xvid, etc. doesn't qualify as video editing either, so in that sense, RAID 0 is a waste. I doubt I'll ever use it again.

I notice a big improvement going from a single drive to a 3-drive RAID 0 setup using vdub. Maybe encoding a DVD to divx doesn't need much. But, how about encoding 4 movies at the same time?