Sustained 25 Mb/s?

[cavalos]

Hi folks and VT users, I want to ask a little question,in fact I think this will be very simple for some of you with experience on uncompressed video.
The fact is I have been wondering how the new Hard Drives respond to uncompressed NTSC digital video and the 25Mb/s data transfer needed for that.
There´s a new western digital HDD called "raptor" that claims a minimum of 40Mb/s (see the link)

http://www6.tomshardware.com/storage/20030501/index.html

So what´s the end of this story...is better to buy 4 disks and a Raid controller or is better to buy a single and faster SATA or a new 320 SCSI?

[Whelkn]

cavalos---

All I have in my system is 1 120 gig western digital drive. Though its not a raptor it does sustain a 40 mb/s data rate. That is not quit enough for 2 layers of real time video. But you could raid the raptor together. That would be cheaper then the scsi drives. Im ordering another WD drive on monday. I cant wait for the added performance. Its hard being a poor college student:)

Jeremy

[kleima]

One drive by itself may not sustain the quoted speed across the entire platter. It would probably work OK until you got the drive really full. The best bet is a SCSI 160/320 stripe of 3 or more 10KRPM drives. Depends on how many layers you want in real time, and how much time you want to spend rendering.

[mgrusin]

These drives are indeed very interesting. Another review/test is at Storagereview.com (http://www.storagereview.com); their graphs show a minimum 45MB/s transfer rate across the platter, which is extremely fast for IDE (but note that IDE drives have traditionally used more CPU cycles to transfer data than SCSI does).

If this series gets big and cheap, these could be a great alternative to SCSI for lower-end Toaster systems. I would still RAID at least two of them together using a 3Ware (http://www.3ware.com/) controller if possible, but for the cost of IDE you can afford to ;)

-MG

[cavalos]

Sorry for this kind of posts, but I´m a very newbie in this field. I have been working with Lightwave for quite a long time but I think is time to raise the bar a bit and start to work with "professional" quality video (in other words uncompressed). That´s why i start to ask this kind of things out of LW forum whit you guys.
As I say I´m very newbie so another question could be (and please forgive my poor english) how many uncompressed and realtime layers are good enogh to work with...Maybe this soun stupid because anyone can say "unlimited are the best!!" but i want to have a "real" and centered opinion from someone who work on this field of what are the best choice price wise.

Best
Christian

[Faraz]

The more the better. But you want to at least be able to do two. This way you can at least get two streams of video out, so you'll have real-time transistions and Pic-in-Pic. But having more layers really helps.

If you can get it, then go for SCSI.

[cavalos]

So, that means two or three HDD´S?

[ScorpioProd]

The drive tests quoted are quite impressive, but another thing to remember is that you want to have excessive margin, since you will be losing some of it depending on how much seeking you are doing, like multiple clips from the same drive versus just reading sequentially on the drive.

You definately get this margin from multiple drives in a RAID.

Also look at it this way, if you are reliably only getting one stream from the drive, what happens with a simple dissolve between two clips? That needs two streams worth of bandwidth to be real-time.

[Matt Drabick]

One thing to consider when building your video array is the fact that, in general, IDE drives wear out much faster than SCSI drives, meaning at some point you may lose the project(s) you're working on unless you have a backup system. Most IDE drive manufacturers have recently shortened their drive warranty from three years to one year.

Over the years I have had several non-Toaster customers (Matrox, etc.) who purchased non-linear editing systems with IDE drives call to say their video array is down due to a defective hard drive. This is yet to happen with any systems built with SCSI drives, specifically Seagate Cheetah SCSI drives. Stay away from IBM UltraStar SCSI drives, they are bad news. But Seagate Cheetah drives are incrediby durable. Yes, IDE drives cost less, but SCSI drives had dropped a lot in price lately.

Having said that, if you still plan to go with IDE drives, then add a large IDE drive (120GB or larger) to backup your projects with. If your video array goes down you will be able to restore any projects once you repair your video array.

Matt Drabick

[SBowie]

Originally posted by Matt Drabick

Over the years I have had several non-Toaster customers (Matrox, etc.) who purchased non-linear editing systems with IDE drives call to say their video array is down due to a defective hard drive. This is yet to happen with any systems built with SCSI drives, specifically Seagate Cheetah SCSI drives. Stay away from IBM UltraStar SCSI drives, they are bad news. But Seagate Cheetah drives are incrediby durable.Matt Drabick While I agree that it's likely SCSI drives are manufactured to higher tolerances and are generally more durable, and I also prefer Cheetahs, I can't honestly say I've never seen failures. Again, while I agree it's more likely with the IBM's, I can think of several of my Toaster clients who have had a Cheetah die (in their video stripeset) over the last couple of years.

[pgrimpo]

I had a Cheetah Die. The way I got it back, amazingly, was to actually freeze it in the freezer. I took out the frosted drive, threw it in the RAID and booted up. Started copying files until the drive failed again. Froze it for a few hours and did it again. Amazingly I got all my data back!

I am having luck running IDE's (Maxtor 7200 8MB Cache) in a RAID on a 3Ware card. I have two 4-drive arrays. The only problem is that the MTBF on IDE's is very low and I have had some die. Now I will be putting up a 1+TB "Active Backup" server RAID array to nightly synch my files to. This backup will be redundant so the most I could lose would be a day of work. Actually, all like 16 of these drives is going to be much cheaper than a decent SCSI array. :)

-Grimps

[darenu]

Wow. Freezing a hard drive for recovery? That's a wild one! Where'd you get that advice?

I've not (yet:rolleyes: ) had a Cheetah go down. My Medea 4/150 drive set just crashed for the third time in 2 1/2 years :( . Medea's been great in fixing, recovering, and even upgrading the drives inside, but I can no longer count on it for mission-critical projects. Fortunately I only use it on my older Matrox system.

[ldituri]

While some IDE hard drives & controllers are useable Scsi is still the recommended drive subsystem.