In a bid to shrink proportions without sacrificing speed, Seagate has introduced the Savvio line of 2.5" SCSI hard drives. These diminutive drives are not only 70% smaller than 3.5" drives, they also spin at 10K-RPM and boast lower seek times than their full-size counterparts. Seagate also claims that the Savvio family consumes less power and makes less noise than other SCSI drives.
As a small form factor enthusiast with a soft spot for SCSI, I couldn't let Savvio go unscrutinized. I've run one of these tiny drives through our usual gauntlet of storage tests against five full-size 10K-RPM alternatives. The results are both surprising and inspiring. Read on to see how well the Savvio stacks up.
Meet mini me
To put the Savvio into context, let's start with a look at how the drive's specs compare with Seagate's 3.5" Cheetah 10k.6 SCSI drive.
|Maximum internal transfer rate||752Mbits/sec||841Mbits/sec|
|Maximum external transfer rate||320MB/sec|
|Average sustained transfer rate||52MB/s||59.9MB/s|
|Average seek time (read)||4.1ms||4.7ms|
|Average seek time (write)||4.5ms||5.3ms|
|Average rotational latency||3ms||2.99ms|
|Available capacities||37, 73GB||37, 73, 147GB|
|MTBF||1,400,000 hours||1,200,000 hours|
|Warranty length||Five years|
|Dimensions||15 x 70.1 x 111.7 mm||25.4 x 101.6 x 146.05 mm|
Right off the bat, there's evidence that the Savvio might not be quite as fast as Seagate's full-size 10K-RPM SCSI drive. The Savvio's maximum internal and average sustained transfer rates are slower than the Cheetah 10K.6 by more than 10%. However, the Savvio boasts quicker seek times that could help balance things out. On paper, the Cheetah has an edge when it comes to lengthy, sustained transfers, but the Savvio looks better suited to workloads with more random access patterns.
While its transfer rate and seek time specs differ from the Cheetah, the Savvio shares its big brother's 10K-RPM spindle speed, 8MB cache, and 37GB platter capacity. The Savvio is only available in 37 and 73GB capacities, though. With Cheetahs available up to 147GB and new 10K-RPM SCSI drives from Maxtor and Hitachi Global Storage pushing 300GB, the Savvio has a definite disadvantage in storage capacity per drive.
Savvio drives are a little less than 70% smaller than 3.5" disks by volume and less than a third of their weight. To put that in perspective, a single Savvio is roughly the size of a deck of cardsyou need three Savvios to approach the volume of one 3.5" hard drive.
In certain RAID configurations, the Savvio's smaller stature can also make up for its limited single-drive storage capacity. Take RAID, for example. A minimum of two drives are required for RAID 1, three drives for RAID 5, and four drives for RAID 0+1 or 10. With Savvios taking up less space, it's easier to squeeze multi-drive arrays into small enclosures. Heck, a three-drive Savvio RAID 5 array takes up roughly the same volume as a single 3.5" hard disk.
Apart from its RAID-specific benefits, the Savvio's smaller form factor also contributes to lower power consumption. The drive's lighter platters require less energy to spin, allowing Seagate to use a much smaller motor than on 3.5" drives. Seagate claims Savvio consumes 44% less power than a typical 3.5" 10K-RPM SCSI drive under load. For large datacenters with rack upon rack of storage, lower power consumption could translate to a significant savings over time. Lower power consumption also gives the Savvio less potential to radiate heat, although any heat it does radiate will be concentrated over a smaller surface area.