Western Digital My Book Thunderbolt Duo
A Mac's best friend?
Review It's over a year since Apple began shipping Macs fitted with next-generation high bandwidth Thunderbolt ports, and they're now in the hands of millions of punters. But with Thunderbolt peripherals still few on the ground, they're all dressed up with nowhere to go.
Mac aware: Western Digital's My Book Thunderbolt Duo
The trickle of devices that can take advantage of the I/O tech has yet to turn into anything like a Springtime English
drought flood. But, at long last, we have a bit of competition for locally-attached storage. Western Digital has released a RAID-capable Thunderbolt storage device that looks excellent value.
The Thunderbolt Duo comes with two Caviar Green 2TB drives which can be configured in a mirrored or striped RAID array, or as plain old JBOD, giving 4TB. By default they're RAID striped, and formatted with HFS+. Plug in the power adapter and you're away.
WD Drive Utilities handles the mirror, stripe and JBOD configuration options
Incidentally, the WD Drive Utilities features a S.M.A.R.T diagnostic self-test, plus a couple of error checking routines. With only one LED on the front panel – with various illumination and colour modes to remember to show the drive's condition – running the WD Drive Utilities gives a less cryptic status overview.
Anyone familiar with WD's two-disk NAS range will feel at home: it's the same case style. Including the nice pop-up lid, allowing easy access to the drives. These sit in a cage and can easily be pulled out, as with the NAS range.
Chaining up multiple Thunderbolt devices looks impressive, but at around £40 a cable it gets expensive very quickly
Setting up Thunderbolt Duo was trivial - but buyers beware: the box doesn't include a Thunderbolt cable, and at £39, this isn't cheap . I took it for a spin in various combinations but also as an exFAT formatted disk running Windows 7 from a Boot Camp partition on the host Mac.
Using the default out-of-the-box configuration, the Thunderbolt Duo offers some seriously stonking bandwidth. Three large test files, including a couple of ISO disk images and totalling 11.84GB, could be written to and from the disk in under a minute. I clocked 55 seconds for a write, and 58 seconds for a read. In mirrored configuration this dropped a little to 89 seconds to complete the write. But still pretty impressive.
Thunderbolt thoroughbred: no other interfacing offered but the two connectors enable daisychaining
I also threw a data set of mixed-size files, that's much more typical of a regular backup, at the Duo. This included a copy of a well-used user folder, and comprised 25,141 files totalling 6.74GB. In striped configuration this was written in just 70 seconds.
Thanks to Thunderbolt, long backups are completed in the blink of an eye, and real-time editing of large files can be performed on locally-attached storage without the traditional performance penalties.
CrystalDiskMark 3 Results
Apple supports Thunderbolt in Boot Camp for Windows users, although the performance suffers
I also cranked up Crystal Diskmark 3 – and the results...? Meh? Meh. No, that's what I thought, too. This is on a par with a USB thumb drive; the Windows drivers supplied aren't really ready for prime time.
Back on Mac OS X, tests took slightly longer with the Duo configured for RAID mirrored - not surprisingly, as two copies of the data are being written. Even so, copying time was not seriously longer. The ISO test set was written in 89 seconds (vs 55 for striped) and the small-files set in 97 seconds. From these tests at least, it averages out at around 215MB/s for the large file stripe write and 133MB/s when mirrored. Both drop to about half their respective scores with the small file writes.
Unscientific, yet typical, everyday copying task results
Impressively, the Mac's Activity Monitor utility barely showed any incremental CPU strain during the reads or writes. The unit itself remains cool and quiet. It's nice to find a manufacturer who realises that heat rises, and puts the ventilation grilles where they should be.
The software is straightforward, and I only detected one minor glitch. Attempting to change the RAID configuration, the RAID utility fails if the drive is already mounted.
Disk removal is the same for all current My Book Duo drives – note the ventilated lid
It's very fast, and if you edit large media files then Thunderbolt storage must be on your shopping list, given that it leaves the CPU unflustered. Yet in more typical real-world scenarios – with smaller individual files sizes – it's fair to say that with USB 3.0 drives consistently notching up over 100MB/s, Thunderbolt has some serious competition to win over mainstream users. ®
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