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HGST Deskstar 6TB NAS Hard Drive

Thanks to OWC for making the 6.0TB 7200RPM HGST Deskstar NAS model 0S03839 available for testing. About $319 as this review was prepared.
The 4TB HGST Deskstar 7K4000 was a stalwart offering used extensively by MPG for several years. Now (late 2014) Hitachi’s 6TB HGST NAS hard drive ups the ante by 50% on capacity and 50% on performance as well. A sweet combination.
A capacity of 6TB is enough for roughly 120,000 36-megapixel RAW files from a Nikon D810. By which time the shutter is well on its way to failing. With high quality JPEGs, it would be roughly 4-5 times that capacity, or more pictures than most people have ever shoot in a lifetime.
Performance as a drive fills up
Even if storage needs are significantly less than 6TB, use of a 6TB hard drive provides much higher performance than a smaller drive, see:
Why You Need More Space Than You You Need and Larger Hard Drives Are Faster Than Smaller Ones, and see the performance tests below.
Sustained transfer speed is the metric most important for many users, and especially for opening large files in Photoshop and similar. Write performance declines very consistently across the drive; see Larger Hard Drives Are Faster Than Smaller Ones, so partitioning to guarantee the fast slice is one optimization technique if the entire capacity is not needed in one large chunk.
Backup and large hard drives
See Cloning as a Backup Strategy. Don’t even think about using a 4TB drive as a main drive without a disciplined backup strategy. If you can store all your Stuff on one drive, think about what it would mean if that drive failed!
Auditory
The drive produced no noise above the level of any of the other hard drives.
Test of entire capacity
The DiskTester fill-volume command writes 1000 files to fill the volume to 99% capacity, then reads those 1000 files back. The resulting data can be graphed to characterize the performance across the drive, as shown here.
disktester fill-volume hgst6
Hard drives are not media-checked from the factory. Your smart move is to run a full DiskTester fill-volume on any new hard drive, to ferret out any performance or reliability issues, which a graph can show.
Performance is stunning, averaging 174MB second across the drive capacity, the fastest hard drive MPG has yet tested as of late 2014.

MB/sec for 1000 files across the 6TB capacity
disktester fill-volume
Compared to its HGST 8TB Ultrastar He8 sibling, the HGST 6TB Deskstar NAS holds a performance advantage out to about 2.7TB of capacity utilization—impressive!

Test of entire capacity
Tested using DiskTester:
disktester run-sequential-suite hgst6
Even 32K transfers run with alacrity, an important consideration for some work.
Peak speed is almost reached with 128K transfers, with 256K transfers sealing the deal. This is an outstanding performance.

disktester run-sequential-suite