Edit Expertise: Storage Shootout
Feb 1, 2008 12:00 PM, By Dan Ochiva
Testing two external storage array options for today's content producer.
Connected via an eSata port, the SimpleTech Duo Pro drive attained average read times of 118.8MBps, far faster than a FireWire 800 connection could deliver. Read speeds were also flat over most of the drive array, a sign of an efficient array (top red line). HD Tach test courtesy of Simpli Software.
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For example, let's look at HDV signals, which move about 3.7MBps per stream. A recent issue of one production magazine stated that a user could figure out what sort of drive array he would need by taking the highest data rate he would regularly encounter — let's say that of HDV — and multiplying it by the number of content streams (video, graphics, audio) he'll be moving to work out which type of drive array would be adequate. A drive or array capable of reading and writing around 15MBps should enable you to handle multiple-stream HDV editing.
We should all wish that it would be so simple. Take the G-RAID2 with its FireWire 800 connection for example; the company states compact array can deliver 75MBps sustained throughput. As before, let's do some similar math: divide that number (75) by the per-stream HDV rate (3.7). You should be able to edit around 20 streams of video at once! So why does the G-Tech site list the array as capable of four streams of HDV as its minimum capability, and not much higher?
“When talking about multiple streams of video, it's not as simple as adding up data rates,” says Pete Schlatter, vice president of marketing at G-Tech. “The big variable that is added to the equation is seek time — the time it takes for the drives to seek between the different video clips. We give the minimum stream count you will achieve on all our products. In other words, the G-RAID is capable of doing many more streams — if they are all very close together on the drive. We test our drives by creating multiple partitions across the drive, then place clips on the inner, mid, and outer partitions. This would be a worst-case scenario in editing — but that's where we come up with our specs.”
Schlatter also mentions another real-world technical gotcha that you can't always figure out by just looking at the specs. Because of processing overhead, some of the new HD codecs in use limit how many streams the processor/editing app can decode in realtime, thus slowing down reads/writes and the system as a whole.
SimpleTech Duo Pro Drive
Fabrik's SimpleTech Pro Drive line of desktop storage is the new kid on the block. The slick matte-silver plastic cover indicates that the company is as savvy about external product design as it is concerned about the innards.
Disk size and connectivity options mark the differences within the lineup. The Simple Drive (500GB or less) uses a USB 2.0 interface. The Pro Drive (1TB or less) offers USB 2.0 and eSATA (SATA/300) interfaces. The Duo Pro Drive (in 1TB, 1.5TB, and 2TB versions) offers USB 2.0 and eSATA interfaces. The drive, however, only ships with an easy-to-come-by USB cable — not a pricier, harder-to-find eSATA cable. That type of heavy-duty external cable is key because the drive can't use the standard internal SATA cable, which employs a different plug.
The model I tested, the 2TB SimpleTech Duo Pro Drive, comes in a silver plastic chassis, with a good-sized disk activity light on the front. The back end includes USB 2.0 and eSATA connectors, a recessed DIP switch for either RAID 0 or RAID 1, a Kensington lock slot, an exhaust grill for the temperature-controlled fan, and a recessed reset switch. You also get preloaded Fabrik Local Backup software, Fabrik Ultimate Backup (a 2GB account for online storage), and USB 2.0 and eSATA cables. This configuration uses two 1TB 7200rpm Hitachi drives, and it includes a three-year warranty. The drive can be set up in either a vertical or a horizontal position; subtle indents in the side allow you to stack multiple drives.
Fabrik might want to take some cues from new stablemate G-Tech, however. Unlike the G-RAID2's tough enclosure, the lightweight plastic Duo Pro chassis didn't hold up too well to even the minimal wear of my review, showing scratches before long.
As with the G-RAID2, the USB 2.0 port on the Duo Pro delivers what are pretty minimal read/write results for today's world (I ran all tests as RAID 0). While there are reports that a fast USB host can achieve 40MBps, my tests topped out at 32MBps — a bit slower than the USB 2.0 transfer of the G-RAID2. If you've got lots of straight transfers to do, such as backing up a work drive, that tops out around 11.5GB an hour.
However, the eSATA connection saved the day. I plugged into one of my motherboard's free SATA ports, ran the long cable out the back of the PC, and then plugged into the Duo Pro array's eSATA port. The speed boost made this drive an entirely new beast. (This is a jury-rigged setup. Ideally, I should use an external SATA port, but my PC didn't include one.)
The new connection delivered a substantial 118.3MBps read throughput, far surpassing the performance of FireWire 800. (I used HD Tach's “Long Bench” test, which employs larger 32Mb sectors to represent reading from large files such as images or video clips.) This is enough to playback a stream of uncompressed 10-bit SD video (60i), or four streams of DVCPRO HD.
To some, eSATA remains a consumer connection standard. It does have its limitations. Up to 63 FireWire devices can be daisy-chained together, while each eSATA requires a separate port connection. FireWire also supplies power to devices that don't use much juice. FireWire devices can be networked, too, because they can carry an IP address.
But for sheer speed and throughput, you can't beat eSATA-connected arrays. I transferred 50GB worth of still images and video in 23 minutes, or at a rate of about 130GB per hour. Here's one reason why: USB and FireWire devices convert the data stream between the external interface and the internal IDE- or SATA-based drives. But because SATA interfaces are featured on most new hard drives, only a simple converter between the internal and external connectors is required in the housing, enabling the outboard device to run at the same speed as an internal SATA drive.
External SATA-connected arrays might be coming of age for an additional reason. Until recently, it cost considerable CPU resources to achieve high-speed results without using a specialized RAID card. (RAID cards offload processing to chip sets on the card.) However, as today's computers move to multiprocessor CPUs, those processor hits are minimized. One or two free CPU cores can tackle the RAID processing job in the background. That means you can get close to hardware-like RAID performance without the added expense of that specialized card.
Want the security of a RAID 1 array, which mirrors your data but effectively halves your storage? Simply flick the DIP switch (tiny and recessed) on the back of the Duo Pro Drive from RAID 0 to RAID 1. For Windows XP users, you'll need to access the Windows Disk Management utility to manually partition and format the drive.
One other nice touch with the Duo Pro: It ships with two levels of built-in backup software and services preloaded on the drives. The local backup software is pretty straightforward, offering onsite protection via regularly scheduled backups. Fabrik Ultimate Backup, however, offers a Web 2.0 approach by including 2GB of online storage for free.
For $5 a month, the company offers what it calls “unlimited” online storage — although you can imagine that unless you have a fast Internet connection for uploading, that might be a little tiresome. But if it's something you can schedule for an overnight upload, it might be a good — yes, even simple — way to use today's latest technology. At a $799 list price for 2TB of flexible storage, Duo Pro is a pretty good deal.
There are now many competing drive array systems to choose from. I chose to look at offerings from a well-regarded industry veteran, G-Tech, and a newbie, SimpleTech, that started in the consumer realm. Both make good gear that differ mainly in their connection capabilities. Considering that the two companies are now one, Fabrik might be a good place to start your search for usable, well-priced external storage.
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