WD Elements 4TB - performance drop after re-partitioning

WD External Drives WD Portable Drives
7

Now the ghost is out of the box. The culprit seems to be Device-Managed Shingled Magnetic Recording (DMSMR).

I did a lot of reading and investigating and as it turns out my WD Elements 4TB external USB drive contains a covert SMR disk. This was nowhere to be found on the box nor any spec sheet. WD promised to be up front about where they use SMR, but they were not about their WD Elements 4TB external drive and are covertly shipping SMR disks in their Elements line.

How did I find out? Analyze your disk with CrystalDiskInfo.

My WD Elements 4TB box carries a sticker: WDBU6Y0040BBK-EA (on sticker on the box)
CrystalDiskInfo reports:

Enclosure : WD Elements 2620 USB Device (V=1058, P=2620, sa1)
Model : WDC WD40NDZW-11A8JS1

When I search on the model then I find:
WD40NDZW-xxMR8Sx/xxA8JSx 4TB (4/8) ::
“Not For Resale” (5400RPM, 128MB cache, USB 3.0 interface, Advanced Format, Shingled Magnetic Recording, 15mm z-height)
[source]

There you have it, you’ve bought an SMR disk without knowing it.

Now WD has a lot of explaining to do.

  1. Why is performance down by 1/3 after re-partitioning and re-formatting for random writes?
  2. Is the disk after a full format under the impression that it’s full, and will performance be down the drain because it is only doing 256MB zoned block rewrites?
  3. Does alignment have any meaning in Device-Managed Shingled Magnetic Recording (DMSMR)?
  4. Does bad block checking (full format) have any meaning in DMSMR?
  5. What happens when you unplug after safe hardware eject? (there was an unknown blinking patters going on after safe eject, which I now think might have been garbage management, buffered writes by the internal drive management software). Is it now corrupted?
  6. What are the blinking states of the drive (there is no explanation in the short manual to be found).
  7. What is the longevity of data stored on an SMR drive (vs a PMR drive)?
  8. How can one partition into multiple partitions and format without loosing performance?
  9. How to manage the drive for optimal performance
  10. How to configure the drive for optimal usage under Linux
  11. It is complicated and new firmware. Are there any firmware updates (will you get them if there are any)?

Can anybody show me to:

  • a proper manual?
  • a decent spec sheet about the drive ( WD40NDZW-11A8JS1 )?
  • an in depth explanation about their DMSMR implementation

With SMR there are a lot of unanswered questions. Furthermore SMR has ZERO benefits for the user over PMR (but it does have performance and reliability downsides). Are there any WD Elements 4TB drives with PMR disks inside? Ask yourself do you want to have all these uncertainties with your precious data storage?

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