View Full Version : To RAID or not to RAID...


Mike Buchinger
January 28th, 2003, 03:04 PM
I recently purchased one of the Western Digital 80Gig hard drives with 8MB of cache. I initially bought it to be a stand alone video/audio drive, seperate from my operating system/application drive. I'm evaluating a couple versions of editing software before I decide what to buy (Avid, Premier, etc). The more I read, the more I wonder, before i go too far, if I should buy another drive and a RAID controller and run a RAID 0 array with 80gig drives.

What will I gain by running RAID performance wise? What about the failure rate and losing all data? I'm generally more looking for opinions and experiences. I'm running an AMD Athlon XP 1800+, with 512MB of DDR333, and ATI Radeon 8500, and Maxtor DX 60GB system drive, and now the newly added Western digital file drive.

I recently read an article that really scared me about losing my data if a RAID drive crashed. But at the same time, if my file drive crashes, I'm just as screwed. The more drives, the more probability for failure right?

Thanks,
Mike

Brian M. Dickman
January 28th, 2003, 03:25 PM
Yes and no. There's lots of places that you can go to read about RAID modes in general, but to summarize (and oversimplify): RAID0 gives you double the performance, while risking either of two drives going out and ruining your data. RAID1 is sort of the opposite, it mirrors two drives, so you get single drive performance, but if one drive goes out you have a second with full data integrity. Most IDE RAID controllers also offer RAID0+1, which is 4 drives, mirrored and striped. So you get twice the capacity of one drive, twice the speed of one drive, and twice the backup. There's also RAID5, but that scheme is mostly reserved for bigger SCSI arrays, and is only worthwhile with 5 or more drives.

What you choose to use is a balance of personal paranoia, personal need for speed, and personal checkbook.

Rob Lohman
January 28th, 2003, 03:49 PM
That is correct, however you can run raid 5 starting from 3 drives.
With 3 drives you get extra capacity (roughly the size of 2 drives)
and one extra drive that stores error correction information to
recover if one drive should fail.

There are two ways you can do RAID, hardware and software
(you need Windows 2000 Server for this to work). I would not
go with Raid 0. Although you will increase in data throughput
it will never double your speed. And if you loose one drive you
will loose both. Also for DV you will not neet a RAID array. If
you have current 7200rpm drive on a ATA100/133 (UDMA 4-6)
it will definitely be fast enough.

If you infest in two or more harddrives I would either chain
them together to get one large harddrive (you can do this with
most RAID hardware cards or you can do it in Windows 2000/XP
when you upgrade to a Dynamic disk -> not sure if this is server
only as well). Or just use one disk for all your input files and the
other for your projects/output (that's they way I have it setup
at the moment). Or you can go with RAID 1 (mirroring), which
you can also do both in hardware & software, for exta safety.

I think my next setup will feature the following:

- one harddrive for my OS and applications, with following partitions: OS (and programs), swap & misc (for downloading/burning etc.)
- one harddrive for my incoming footage, with following partitions: projects (for all project related footage) & misc (for all other footage)
- one harddrive for project data, with following partitions: project & output (final rendering etc.)

If money allows I will put mirror that last harddisk. If I loose a
project whilst working on it would be a disaster. Original footage
can be re-captured from tape (which I keep!) and the same go's
for my OS & application drive. I perhaps might get a DVD burner
instead though and backup my project on DVD every now and
then. Still thinking about that.

Just my two cents and ideas...

Jeff Donald
January 28th, 2003, 09:50 PM
If all you are editing is DV, you're performance gain will not been much. DV, at 4mb per second is not pushing the limit of a single drive by any means. It may speed up rendering, if your plans call for a lot of it. But overall, the extra expense doesn't translate to real world (editing DV) performance increases. If you're doing HD, that's a different matter.

Rhett Allen
January 28th, 2003, 10:27 PM
While the DV signal of 3.7MB/s is not a big tax on the hard drive, if you are playing several streams at once it adds up quickly because you are requesting data from several different sectors of the drive at once.
I have 4 drives in my machine, a boot drive (system and apps), a backup boot drive which is a copy of my main boot (NOT a mirror, If you mirror a drive, whatever corrupted material hits your primary drive automatically gets thrown onto the mirror also, not good) the backup also holds a copy of my project files as backups. The other 2 are in a ATA133 RAID stripe configuration (hardware). If for some reason I lose the stripe set (which I have when I used IBM DeathStars) I keep my logs backed up in several places (including Zip disk) so with FCP3 (sorry, I am on a Mac) I can just launch the backup project fie and capture the data exactly the same way to replace it. All I'm out is the re-capture time. All of my edits are saved and I'm back at work.
I noticed a big difference in speed when I started using the RAID. Video never stutters, drops, hangs and renders faster when I need to. Sure a single drive would work but the RAID is definitely faster. My RAID transfer speed is usually between 59-63MB/s whereas my single drive speed is about 32MB/s, and these are all ATA133 Maxtor fluid bearing drives.

I think it's a good idea, but then, that's me.

Jeff Donald
January 28th, 2003, 10:33 PM
I don't think it is a waste of money at all. But I think you'll get more bang for your buck if max out your ram. If you've got extra money after that, get a RAID.

Robert Knecht Schmidt
January 28th, 2003, 10:36 PM
Not sure if there are any benchmarks out there for this, but I was under the impression that folks with real time hardware cards would benefit from increased throughput of RAID 0.

Alan Suen
January 29th, 2003, 09:16 AM
IDE RAID really only for Redundancy...not much performance gain.

SCSI is alot better, with Disconnect and Reconnect, Tagged Command Queuing...etc. IDE device have to wait for the whole operation to be completed before it will releases the bus for other transfer....SCSI don't need to with DIS/REC.

My 2 cents worth.

Rob Lohman
January 29th, 2003, 10:55 AM
Alan, if you have a good new IDE RAID card it will increase your
performance. And with good cards I doubt other devices will
have to wait. And if you only have two devices you can but them
on a seperate bus. My Promise Ultra133 card (no RAID, but they
do have them in raid) can even mix different IDE protocols and
speeds without any of them getting in trouble on the same bus
(which was previously impossible for IDE)... so....

Brian M. Dickman
January 29th, 2003, 12:00 PM
Tom's Hardware has done a pretty extensive article series on IDE and RAID. Here's some links:

For the executive summary, Benchmarks:
http://www6.tomshardware.com/storage/20020830/ide_raid2-05.html#test_results

Part 1 on IDE: Basics and Technology:
http://www6.tomshardware.com/storage/20020806/index.html

Part 2: Performance and Data Security With RAID:
http://www6.tomshardware.com/storage/20020813/index.html

Part 3: Using RAID:
http://www6.tomshardware.com/storage/20020830/index.html

Keith Luken
January 29th, 2003, 12:35 PM
DV editing will not really tax your drives, as the capture is firewire limtied and rendering is usually CPU/RAM limited. The real question is SPACE. How much space do you want to use for video at 13GB per hour of video. Have a drive for capture and one to render to is nice or one hugh drive is nice. I wanted large space to have multiple projects on compute rat once so I have 6 drives, 2 x 40GB RAID 0 for OS and apps, then 2 x 80GB RAId 0 for capturing and then 2 x 80GB for rendering and final projects that need to be burned, etc. I used 80GB becasue 120GB was too expensive last year so I raided. If I were doing it today I would just get 120GB or 200GB drives and skip the RAID, you really don't gain much REAL WORLD performance and average latency can actually increase. The WD 8MB drives are great I would get a second just for the space and skip the RAID. My next system I am looking at going 3 drives, 1 80GB WD8MB, and then 2 200GB WD 8MB drives no raid!

Robert Knecht Schmidt
January 29th, 2003, 12:48 PM
"DV editing will not really tax your drives, as the capture is firewire limtied and rendering is usually CPU/RAM limited. The real question is SPACE."

Well, as I said above, this view neglects the demands of real-time editing hardware when accessing more than one stream at a time, as with real time picture-in-picture, or picture-in-picture-in-...^n

Jeff Donald
January 29th, 2003, 03:16 PM
In the ultimate discourse of things Real Time Effects may be hindered by the performance limitations of a single drive. However, the original post concerns the use of AVID or Premiere software and neither uses RT Effects at the DV level. While Analog Video or HD Video would benefit (and RT Streams) RAID usage with DV may not be worth the risk. The added cost of two additional drives (and necessary controller) would only give him marginal performance increases for DV. He would more likely benefit more from additional RAM and at a more modest total expense. The RAM increase would give him more performance per dollar spent.

Gints Klimanis
February 12th, 2004, 04:03 PM
>If you're doing HD, that's a different matter.

Isn't HD still a 25 MBit MPEG2 stream ?

Rob Lohman
February 12th, 2004, 04:11 PM
He was talking about the serious HD work, which is running at
a lot higher rate than 25 mbps HDV is using. It's probably more
running along the lines of 250 mbps.

Gints Klimanis
February 12th, 2004, 04:29 PM
Keith,

Which RAID controller do you use? What I'm really looking for is one card for more IDE channels so that I can run non-RAID alongside RAID. Are you doing this with your controller ?
I'm just trying to speed up my uncompressed video processing.

Thanks to Brian for the Tom's
hardware links. They cite a 100% increase in disk read/write performance using three disks in RAID0, while two disks
offer a 50% increase. Here's the RAID controller they are
using in the benchmarks:

HighPoint RocketRAID ATA133 4044 Channel ~$100
RocketRAID 404 supports up to 8 IDE hard disk drive

http://www.highpoint-tech.com/USA/frcontroller.htm

Rob Lohman
February 12th, 2004, 04:45 PM
Just so you know, you can also buy normal ATA133 controllers
to add to your system for more channels.

Gints: to whom are you asking that?

Keith Luken
February 12th, 2004, 04:47 PM
I use the Rocketraid 404 which is great as I have 4 channels and it has turned out to be one of the most compatable adapters I have used, both the onboard RAID on my Gigabyte 875 board and a Promise FX2000 had major issues with XP with all my adapters and such, especially the onboard CSA Gigabit. The RR404 is rock solid, Ican run RAID sets on their own dedicate chahenls for each drive along side JBOD on the other channels. A very flexible controller. Just be sure to use the latest Firmeware and drivers and it works great. At one point I had 2 x 40GB RAID 0 then 2 x 80GB RAID 0 and another 2 x 80GB RAID 0 all on the same card! Now I run 2 x 80GB RAID 1 and thena 120 GB and 160GB as JBOD all on their own channels!

Mike Rehmus
February 12th, 2004, 08:26 PM
<<<-- Originally posted by Gints Klimanis : >If you're doing HD, that's a different matter.

Isn't HD still a 25 MBit MPEG2 stream ? -->>>

HD at 25 mbps is a new construct for use at the consumer and prosumer level. The JVC camera is the first instance of the standard that was just approved by Sony and the other Japanese camera manufacturers.

The 'big-boy' HD like that used in Star Wars and other movies is way beyond 25 mbps.

Gints Klimanis
February 12th, 2004, 08:41 PM
Ok. After checking the Web, here's an interesting review of the
Promise TX4000 4 channel (8 disk) ATA133 RAID controller,
which sells for about $170 .

http://www.xbitlabs.com/articles/storage/display/promise-tx4000_11.html

There's a nice table that includes mention of performance in Premier 4.2 and Sound Forge 4.0. The interesting thing is that
FAT32 performance on page 12 blows away NTFS performance.

Rob Lohman
February 13th, 2004, 05:41 AM
I'm not that surprised. NTFS is a much more complex filesystem
that does journallig, security, encryption etc. which FAT32 doesn't
do. So therefor it has a lot less to check etc.

But, it won't go beyond 4 GB files which basically means it is
unusable for most types of video work. Also NTFS is much more
robust if something goes wrong.

Gints Klimanis
February 13th, 2004, 03:09 PM
Anyway, I'm going for RAID with the HighPoint 404 four channel ATA/133 RAID card for $120. I just scored a couple of 120G drives (Western Digital, 8MB buffer, 7200 RPM) for $50 each after rebate and will have my friend pick up two more.