By Ned Soltz, February 4, 2008
In the December 2007 issue of DV, I wrote about “rolling my own” RAID and the underlying technologies which continue to make massively fast storage solutions more and more affordable to even more editors.
But, a little follow-up serves as a reason why purchasing a turnkey solution may far outweigh any monetary savings attained by building your own RAID.
My original RAID consisting of two MacGurus Burley Boxes, with each populated with four Hitachi 250-gig drives with a Silicon Image 3726-based port multiplier and managed by SoftRaid for Mac, has been running strong. Even when I broke the data connector of one of the Hitachi drives when installing the port multiplier, I was able to patch the drive with a piece of the broken plastic cover.
My five-drive RAID populated with Seagate 750-gig drives has not been quite so trouble-free. About six weeks after building the drive and completing my article, the Silicon Image software did its job and e-mailed me that my RAID was rebuilding because of a failure of drive 1 (which actually is the second drive in the box since for some reason the software numbers the drives 0 to 4). Before replacing what I thought to be the offending drive, I popped it from the removable enclosure, reinserted it and the drive mounted. I repeated the action several times. Using the Silicon Image software, I designated the drive as the “hot spare” under my RAID 10 configuration. On at least three separate occasions, that hot spare has gone offline, requiring removing and reinserting the drive. I continue to use that drive as a hot spare. But it tells me that my enclosure obviously is intermittent and therefore not totally dependable. But what do I do when I bought the enclosure from a Web site box pusher and my drives one at a time when the local megachain electronics store was selling loss-leader Seagate drives?
I’ll tell you what can be done: Turn to a vendor who offers a RAID with support, a warranty, drives from matched lot numbers and hardware/software customized by a company who understands the difference between storing word processing files and video.
Dulce Systems stands out as a shining example of such a company. Founded by several storage industry professionals who have moved together between companies for the almost 20 years, the Dulce produces a full line of FireWire, eSATA, and direct PCI storage solutions for everything from DV to 2K editing.
I have had the opportunity to use Dulce’s top-of-the-line product, the Pro DQ, for several months and put it through its paces. While I did not experience any failures whatsoever during that timeframe, it was definitely reassuring to know that I had a vendor standing behind the product and as well to know that Dulce offers a 42-month warranty on this system — longer than anyone else in the industry.
The Pro DQ enclosure hosts eight eSATA drives for a maximum of 8TB unformatted in RAID 0 configuration. Where it differs from my homebrew RAID (or even from less costly devices from Dulce and other vendors) is that it interfaces to the PC or Mac via a direct PCIe or PCIx controller card. The controller card itself is a small computing device with an Intel IOP341 800Mhz processor, 1MB SRAM and an internal bus speed of 6.4GB/s. In other words, the card is operating at the speed of the bus rather than being slowed down by a conversion from the bus to an eSATA bridge card. The chipset on the card and the drive backplane supports JBOD, RAID 0, 1, 3, 5 and 6.
ABOVE: Dulce’s RAID set hierarchy window.
Dulce ships the Pro PQ configured as RAID 5. They contend that this is the optimal redundancy for digital video to maintain both an extremely fast data rate as well as the least possible loss of useable space. Note that in a RAID 5 configuration, the RAID maintains parity on drives rather than a mirroring scheme as in the RAID 10 configuration of my homebuilt devices
. To calculate the effects of parity, take away one drive from the config and that gives you roughly the useable space on your RAID. RAID 6 provides double parity and the expense of one more drive. Dulce claims that in RAID 5 configuration, the system will deliver 570MB/s as opposed to 660 MB/s in the unprotected RAID 0 mode. Those data rates should sustain any video frame size editable on the desktop.
The system ships with drives removed and packaged in shock-resistant packaging, numbered sequentially 1 through 8. Just insert drive 1 in the top slot and so on down the line. The unit is heavy and well-ventilated with virtually silent fans. The controller card (I tested the PCIe model on a MacPro) installed easily into a slot which then I configured as a 4-lane PCIe slot using Apple’s utility. Having experienced any number of accidental disconnects of non-locking eSATA cables, it was reassuring to see that the card and drive unit were attached by two latch-locking 4-lane connectors. Software installation was a snap. The drive mounted on the desktop immediately as one volume.
RAID management is accomplished by a Web-based interface which controls formatting, settings, notification management and all other functions. It is through this interface that one can select the RAID protocol. To remain consistent not only with Dulce’s recommendations but also with what most editors would common maintain, I left the default RAID 5 settings.
Before capturing any video, I ran the AJA System Test software to verify Dulce’s speed claims. Numbers for SD 720x486 were off the chart. But you’re not going to invest in a RAID such as this strictly for local furniture store going-out-of-business-sale commercials in Beta SP. More real-useages scenarios are HD and 2K. With a 1920x1080 10-bit frame size and 2GB file size, the system test returned write speeds of 634.4MB/s and read speeds of 553.5MB/s. I achieved eight layers of uncompressed HD in Final Cut Pro before I got the red render line.
ABOVE: The AJA system test screen.
Testing for 2048x1556 10-bit RGB frame sizes with a 4GB file size, data rates remained virtually identical to 10-bit uncompressed HD. As a point of reference, 2K (1556) video at 23.98 fps has a data rate of about 308 MB/s and if by chance anyone would be editing 2K 29.97 (I don’t know why), that rate would climb to 382MB/s. Statistically speaking, then, the RAID should handle 2K without breaking a sweat.
In order to test that, I acquired footage shot at 2K in the Red camera and, using Red’s software, converted to 2K footage. I dropped those files into FCP timeline and played. The result was not a single dropped frame.
Dulce has demonstrated a PCIe expander box which would allow multiple controller cards to chain to multiple RAIDs. This allows for virtually unlimited storage expansion of securely redundant data. Note, however, that this is not a SAN solution. It would be a welcomed extension of this technology to make this fast and relatively economical storage solution available across a network.
Dulce Systems has delivered a winner with the Pro DQ. It is available in configurations from 2TB to 8TB and with the upcoming expansion technology offers virtually unlimited size. The software is flexible and allows for easy reconfiguration and rebuilding of the RAID. The device itself is sturdy and quiet. The connections are secure. Support is knowledgeable of video matters and speaks the language of our industry.
The Pro DQ is the other extreme from the inexpensive technologies I have demonstrated previously, but, for those editing in this HD and 2K range, it should be a serious contender for your precious data.
Pro DQ
$4,799 (2TB) $8,399 (8TB) >
DV Score:
Pros:
An affordable, well-built solution that performs without a hitch yet also has a great warranty.
Bottom Line:
Dulce Systems has delivered a winner.
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