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swoolf
Nov 12, 2003, 11:09 PM
Hi all -

I'm setting up a storage/working solution to provide scalable high-speed storage for digital video editing. In researching, I cam across some unexpected information -- that in real world useage, gigabit ethernet is actually faster than firewire.

This surprised me because, while I know the theoretical throughput is faster with gigiabit ethernet, I thought the overhead of a local bus, gigabit switch, and file server bus would make a fireweire 800 disk plugged directly into my local machine a better solution.

Anyone have any experience working with digital video files over gigabit ethernet? What do you guys think is the best way to go in terms of long-term scalability and cost?

Thanks,

Steve

LethalWolfe
Nov 12, 2003, 11:28 PM
Are we talking DV or uncompressed video here? Also, you might find better answers over at www.creativecow.net (http://www.creativecow.net).


Lethal

e-coli
Nov 12, 2003, 11:39 PM
Gigabit ethernet seems like a really strange choice. I wouldn't be inclined to even try it as a solution, since you're dealing with a downstream BUS. I would think that the demands of video (constant back and forth) would be a nightmare over ethernet.

With FW800, at least you're dealing with a local BUS.

Now, fibreChannel...that's a different story. But Ethernet? I don't think it will work. Save your money. Go FW800.

G5orbust
Nov 13, 2003, 12:06 AM
Originally posted by e-coli
Gigabit ethernet seems like a really strange choice. I wouldn't be inclined to even try it as a solution, since you're dealing with a downstream BUS. I would think that the demands of video (constant back and forth) would be a nightmare over ethernet.

With FW800, at least you're dealing with a local BUS.

Now, fibreChannel...that's a different story. But Ethernet? I don't think it will work. Save your money. Go FW800.

I agree. Firewire is made to handle a sustained throughput of data. Thats why Firewire is prefered over USB2 for high speed video transfer; USB2 may be rated faster but Firewire beats the pants off of it because FW's sustained throughput is so great.

CAT-5e networking would be fine if you were just deposting files onto a server, but if you plan to edit off of a disk over a network, make that network a FW800 network.

swoolf
Nov 13, 2003, 12:07 AM
I don't intend to use the file server as a scratch disk, just as a means of mass storage.

Maybe my question wasn't really clear -- rather than daisy chain 2 or 3 firewire drives as a means of storage, is using a file server connected with gigabit ethernet a viable solution for moving around these enormous files of compressed and uncompressed video?

I'm using a G4/466 file server connected over a gigabit network to two Powerbook 17 editing machines with 80GB internals. Each of the Powerbooks has a Firewire 400 attached right now, but they're running out fast. I want a longer term solution than to stack up firewire drives.

My thinking was to use the internal drives as the scratch disks and the file server for storage.

Thanks for the input.

Steve

Powerbook G5
Nov 13, 2003, 12:20 AM
I wouldn't rely on ethernet for large file sized data transfers because the latency would drive me up the wall, not to mention the added complication. I'd just go for a nice FW 800 solution.

swoolf
Nov 13, 2003, 12:22 AM
Fort futher clarity - the gigabit network has not yet been set up. So I didn't have any ability to test throughput.

Steve

swoolf
Nov 13, 2003, 12:31 AM
Bad latency even with gigabit? The numbers I've read on the internet seem to indicate that file transfer times are actually faster over gigabit networks than on a local bus to a firewire 800.

Hence the post that started the discussion. Anyone have real-world experience transferring files over a gigabit network?

Also, from a practical point of view, let's say I have room for 4 internal drives in the file server. In terms of cost at present price levels, it's a significant savings over FW800. FW800 prices should start dropping soon of course, but then, so should the prices of large internal ATA drives (180GB and up).

Steve

Powerbook G5
Nov 13, 2003, 12:39 AM
I haven't used gigabit ethernet personally, but theoretical results and real world results are two very different beasts and I have never used an ethernet setup that offered a consistent high speed transfer.

WannabeSQ
Nov 13, 2003, 01:07 AM
I would say, that if you have local Internal HDs and FW drives for editing and short term storage, that even 100baseT would be good enough for a long term backup type solution. Gigabit would just make it a hell of a lot easier. Not to mention, that 200GB HDs with 8mb cache are goin for $170, and a file server computer can hold a whole array.

As a side note, I would imagine that a PC with Gig E could do the job, and you could get a large server case and load it up with extra HDs, and have room to grow.

beerguy
Nov 13, 2003, 10:17 AM
Transferring files is probably faster. Whether it is suitable for real time streaming is another issue entirely. TPC/IP is a unrealiable protocol; it expects packets to be lost and re-sent. The other issue you have is that there is no mechanism to make packets route in the correct order. In a realtime environment like DV, that means frame loss. The only way around the later is a ton of system RAM to buffer the streams. If your DV app is looking for data and it's not buffered - you're hosed.

GigE works well for file level access you want FW, SCSI or fibre channel for block level access; i.e. working within a file.

tomf87
Nov 13, 2003, 10:23 AM
Using a single disk is going to slow things down considerably. Depending on cost, you could use an XServe RAID and use Fibre Channel to connet it. This would allow you to expand as your needs grow. In addition, you could implement RAID for redundancy, just make sure you select the RAID type that best suits your needs.

I just deployed a new SAN using Ultra320 SCSI drives, and the thing is lightning fast. Of course, it's not Apple, but regardless of the manufacturer, the speeds of SCSI arrays over ATA is very noticeable.

mactastic
Nov 13, 2003, 10:31 AM
Fibre Channel may be right up your alley. Instead of putting money into a FW800 network, get a fiber channel card and a G5/X serve RAID. Better back-up security for those mission-critical files, and from what I have heard Fiber Channel is FAST!

Look beyond Apple too, you might save some money. I think I'd want some kind of RAID setup if I was in your shoes.

swoolf
Nov 13, 2003, 11:16 AM
Unfortunately, anything other than software-based RAID is not in the budget. I'm looking at an older G4 with Gigabit Ethernet as the file server and utilizing the already built-in technology in that machine and the two 17" editing stations.

It's really between Firewire and Gigabit to make a budget-conscious determination about storage. Firewire's attractive because of its plug-and-playability, where as the long-term useage of gigabit ethernet and a file server may work out better.

I'm leaning towards the file server solution. FW800 drives are very expensive right now. 180GB internal drives can be had for a $1 a gigabyte and under.

Some other real-world testing I've read indicates that transferring multi-gigabyte files over a switched gigabit ethernet network is slightly faster than Firewire 800 (techtv.com). If that's accurate, it's another reason to centralize file storage.

Also, I read that streaming video over Cat6 cables (or even 5e) is more than acceptable.

Steve

yamabushi
Nov 13, 2003, 11:32 AM
Use Cat6 ethernet cable when you can. It only costs a bit more than Cat5e when bought by the spool. Avoid plain Cat5 for gigabit networks.

Daniel Viney
Nov 13, 2003, 11:46 AM
Hi,

I have some realworld experinece transferring large amounts of OMF video files (large but under 2 gigs per file) over gigabit ethernet between Avid systems to a server. Transfers were at least as fast and as responsive as transfers to local firewire 400 drives (haven't tried firewire 800). The clients were running OS 9 not X and the server was hardware RAID based, which may be significant factors. Friends of mine even run ProTools TDM sessions from the server over gigabit ethernet without problems (though I can only guess they are doing very limited things, as this really seems like a bad idea).

- Daniel

finner
Nov 17, 2003, 11:59 PM
My gigabit network can push around 20/MB/sec. Latency isn't too bad. this number is from transferiing large files (over 500MB) from a 733 quicksliver to a 1.25 MDD. The hard drives aren't the problem, but maybe a faster chip would imprreve things. By my math, Gigabit should be 125MB/sec. Okay, I've heard of overhead, but how about 50%?

tomf87
Nov 18, 2003, 07:54 AM
Originally posted by finner
My gigabit network can push around 20/MB/sec. Latency isn't too bad. this number is from transferiing large files (over 500MB) from a 733 quicksliver to a 1.25 MDD. The hard drives aren't the problem, but maybe a faster chip would imprreve things. By my math, Gigabit should be 125MB/sec. Okay, I've heard of overhead, but how about 50%?

20 MB/sec is terrible for gig. I can push that through easily on my 100 Mb network.

For some reason, I always find that testing different settings of autonegotiation help different computers. For example, I get great results by nailing 100/Full on a 3Com switch and a Compaq gigabit server adapter. However, when I replaced the 3Com switch with a Cisco, nailed the Cisco to 100/Full, throughput dropped. Setting the server to Auto brought the levels back to life.

Another thing to do is eliminate the network with a crossover, and see what the results are. It could be that a firmware/IOS update for the switch will help or even just nailing the ports.

EDIT:

Oh, and I've never seen overhead of 50% on an ethernet network. If I can push 13 GB in 10 minutes on 100 Mb, that certainly disproves the overhead being so large. I know I'm only getting roughly 21 MB/sec here, but with gigabit, that figure should be much larger.

Tom

Powerbook G5
Nov 18, 2003, 09:13 AM
There are so many factors in determining your ultimate speed with ethernet, though. You need good, quality equipment because cheap hardware can make a huge difference, you need to make sure it is all updated, you need high quality ethernet cable (especially for gigabit), make sure your settings are set correctly, make sure it is connected correctly, etc. I've noticed that even the slightest thing can adversely affect the performance of ethernet.

finner
Nov 19, 2003, 12:02 AM
Originally posted by tomf87
20 MB/sec is terrible for gig. I can push that through easily on my 100 Mb network.

Another thing to do is eliminate the network with a crossover, and see what the results are. It could be that a firmware/IOS update for the switch will help or even just nailing the ports.

EDIT:

Oh, and I've never seen overhead of 50% on an ethernet network. If I can push 13 GB in 10 minutes on 100 Mb, that certainly disproves the overhead being so large. I know I'm only getting roughly 21 MB/sec here, but with gigabit, that figure should be much larger.

Tom

Thanks for the suggestions. I tried pegging the speed at 1000- full and on one then both machines. It took the speed down to 16MB/sec. Crossover is a good idea but it involves alot of computer lugging. I'm hoping to gain some ground with less physical work. My switch is a GX5-800. I hope this isn't the problem. I kind of like Asante. What I did notice, is that while my main cabling is Cat 5e, the patch cords are just Cat 5. The switch does recognize the cpus at 1Gb.

new patch cables?

I also had a question about the 20MB /sec speed of your 100Mb/sec network. Isn't 20MB = to 160Mb?
Thus exceeding the maximum transfer rate?

I'm only looking for 40MB/sec + for now because that tops out my hard drives. Small network...

thanks

finner

tomf87
Nov 19, 2003, 07:28 AM
Originally posted by finner
Thanks for the suggestions. I tried pegging the speed at 1000- full and on one then both machines. It took the speed down to 16MB/sec. Crossover is a good idea but it involves alot of computer lugging. I'm hoping to gain some ground with less physical work. My switch is a GX5-800. I hope this isn't the problem. I kind of like Asante. What I did notice, is that while my main cabling is Cat 5e, the patch cords are just Cat 5. The switch does recognize the cpus at 1Gb.

new patch cables?

I also had a question about the 20MB /sec speed of your 100Mb/sec network. Isn't 20MB = to 160Mb?
Thus exceeding the maximum transfer rate?

I'm only looking for 40MB/sec + for now because that tops out my hard drives. Small network...

thanks

finner

You definitely should go with CAT 5e patch cables. That could be the problem. I don't think older CAT 5 cables are fully qualified for gig operation.

As for my transfer rate, it is due to full duplex. Full duplex, although I still have trouble dealing with this as well, is supposed to give you 100 Mb each way simultaneously (or 200 Mb). I guess that transfer proves it but I still think of 100 Mb as 100 Mb and expect that no matter what the duplex is.