LaCie Little Big Disk 240 GB
|RPM||5400 RPM||7200 RPM||5400 RPM||SSD|
|Capacity||1 TB||1 TB||2 TB||240 GB|
|Devices||2 x 500 GB||2 x 500 GB||2 x 1 TB||2 x 120 GB|
LaCie’s Little Big Disk (LBD) is available in four trims: 1 TB (2 x 500 GB, 5400 RPM), 1 TB (2 x 500 GB, 7200 RPM), 2 TB (2 x 1 TB, 5400 RPM), and 240 GB (2 x 120 GB, SSD). The 240 GB model, which is what LaCie submitted for review, is unquestionably the most interesting. It's the first Thunderbolt-based device we have seen with SSDs in RAID. That's perfect for pushing the interface's performance, providing the company picks the right drives.
LaCie touts the Little Big Disk as a "portable powerhouse," and SSDs drive that message home quite effectively. However, we do end up with critical feedback to pass along. Contrary to LaCie’s product photos, the Little Big Disk requires a separate AC adapter for daisy chaining because Thunderbolt, in its current form, does not supply enough power to run everything off of bus power.
Our enthusiasm is further dampened by the fact that LaCie chose to employ Intel’s 120 GB SSD 320. Don't get us wrong, we've found the SSD 320 to be incredibly reliable. It's just not a great-performing drive. You'd get better benchmarks results from any number of more modern 6 Gb/s-capable SSDs. But before you consider a do-it-yourself replacement, bear in mind that you'd be voiding LaCie's warranty. Four screws on the back of the drive are resin-coated, making it easy to tell if the chassis is opened.
All of LaCie's Little Big Disk models employ the same Intel CV82524EF/L Thunderbolt and Marvell 88SE9182 SATA controllers.
Queue depth appears to have no impact on performance, which is good news if you don't have one of those rigorous storage workloads needed to extract peak performance from many SSD-based products.
In RAID 0, sequential reads even out at ~470 MB/s, while writes peak around 250 MB/s. Using relatively low-capacity SSDs makes it hard to imagine a scenario where RAID 1 would make sense, but we generated those numbers anyway, if only as an interesting comparison to what RAID 0 does for throughput. And, as expected, when we limit the Little Big Disk to the capabilities of a single SSD 320, its sequential reads max out at ~250 MB/s, while sequential writes fall to ~125 MB/s.
Unfortunately, the SSD 320's random performance results are fairly modest, so the numbers we see aren't as spectacular as what you might otherwise expect from a modern SSD. The 4 KB random reads slowly climb from ~20 MB/s to ~130 MB/s, with no correlation to RAID configuration. We see that 4 KB random writes max out at 100 MB/s in RAID 0; RAID 1 achieves up to ~50 MB/s.