Western Digital has started partner sampling of its 18 TB and 20 TB energy-assisted magnetic recording (EAMR) drives. The HDDs utilize WD's up and coming EAMR tech to further improve their storage density, allowing hyperscalers and similar customers to continue improving the density of their storage clusters. WD is on track to start volume shipments of these products sometimes in the first half of next year.

According to an announcement posted by Western Digital, the new 18 TB Ultrastar DC HC550 CMR and 20 TB Ultrastar DC HC650 SMR hard drives have been shipped to a dozen of enterprise OEMs, as well as operators of hyperscale cloud datacenters. This also includes Dropbox, who has been one of the prominent backers of the host-managed SMR technology. Western Digital isn't disclosing the exact number of 18 TB and 20 TB HDDs it has shipped so far, but given the number of potential customers and the very nature of large datacenters, we are likely looking at thousands of units.

The key difference, of course, between Western Digital’s new 18 TB and 20 TB hard drives and their predecessors is usage of the company’s energy-assisted magnetic recording technology. Western Digital has been relatively tight-lipped for a bit now about its ‘EAMR’ tech and just what they're doing under the hood; for the moment the company is only disclosing that it is a subset of its microwave assisted magnetic recording (MAMR) technology. However the company has added that it does not use a spin-torque oscillator, which is a key component of normal MAMR.

One thing to note is that the 18 TB Ultrastar DC HC550 is the ‘base’ model that uses conventional magnetic recording (CMR, which is what HDD makers call non-SMR drives these days), which means it behaves more or less like typical 7200 RPM enterprise-grade helium-filled HDDs. Meanwhile, the 20 TB Ultrastar DC HC650 uses shingled magnetic recording (SMR) with all of its peculiarities.

Overall, the sheer size of the drives does mean that WD's customers will be evaluating factors such as IOPS rates versus the increased size. Since IOPS is essentially constant for a HDD – seek times haven't really changed – the IOPS-per-TB rate has continued to drop with larger drives, with these drives continuing that trend. That especially goes for the SMR drive, of course, with shingling resulting in an even lower IO operation rate. As a result, only select companies – who happen to run software that considers peculiarities of SMR and a lower per-TB IOPS – are expected to use Western Digital’s 20 TB SMR drives.

MAMR aside, both drives are based on the company’s nine-platter helium-filled enterprise-class platform. WD's latest generation enterprise tech incorporates triple-stage micro actuators that are optimized for working in multi-drive environments (e.g., racks). The enhancements of such platforms usually include top and bottom attached motor, top and bottom attached disk clamps, RVFF sensors, humidity sensors, and some other methods to improve reliability and guarantee steady performance. To that end, the HDDs are rated for a 550 TB/annual workloads, a 2.5-million MTBF, and are covered by a five-year limited warranty.

If all goes according to plan for Western Digital, expect to see them shipping the new 18 TB CMR and 20 TB SMR HDDs in volume in the first half of 2020. At which point hyperscalers and other enterprise customers will start their own ramp ups for installation.

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Source: Western Digital

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  • shabby - Monday, December 23, 2019 - link

    Hamr samr mamr eamr, can these guys stop with the buzz words, it doesn't help your dieing breed.
  • TheinsanegamerN - Monday, December 23, 2019 - link

    "dying", not dieing. Also, these larger drives address a growing market of mass storage, something SSDs still cant touch.
  • Drkrieger01 - Monday, December 23, 2019 - link

    While mechanical drives will still fill the need for the next 5 or so years, I have a sneaking suspicion that after it'll be 'cold storage' SSDs. The amount of flash that can be stuffed into a small space these days is impressive, and the 128 layer 512Gb flash modules do carry quite a bit of storage. Once we hit the 1Tb/256 layer, I'm sure capacity restraints won't be an issue
  • rahvin - Monday, December 23, 2019 - link

    Spinning Rust is still way cheaper and will remain way cheaper for mass storage for likely a very long time. NAND prices collapsed because of an oversupply, like the DRAM crash in the early 2010's NAND prices are going to correct, every producer has slashed production and most have ended entire production lines. By the end of 2020 I expect prices to at least double if not triple on NAND.

    In the meantime with these new storage technologies mass storage will continue to be dominated by spinning rust and the amount of storage that's needed in the cloud companies is staggering, demand that couldn't be met by NAND because enough isn't produced to meet it. NAND will likely takeover the consumer market completely, but NAND has mostly already taken over that market so it doesn't really hurt the drive producers. Spinning Rust is frankly the only solution for the exabyte storage needs of the cloud companies, at least for the foreseeable future.
  • Beaver M. - Friday, December 27, 2019 - link

    They have a huge margin for price drops, so you are most likely right. I mean SSDs really have become really cheap, but only up to about 2 TB. After that they are still far too pricey. Compare that to 16 TB HDDs and you have your answer who will still be king for a long time.
  • Korguz - Saturday, December 28, 2019 - link

    spinning rust.. the dumbest term to discribe mechanical hdds...
  • eachus - Thursday, December 26, 2019 - link

    Right. Dieing is cutting a silicon wafer into dice, among other things. Dyeing is what you do to Easter Eggs, or fabrics, among other things. (Not the kind of fabric found in a supercomputer.) Isn't the English language wonderful? As for magnetic disks, they may seem a dying breed, but if you have any sense--and hyperscalers certainly do--currently SSDs should always be in RAID 1, 5, or 10, or backed up by HDDs. Which is less expensive? Depends on the amount of reading and writing done.
  • rUmX - Monday, December 23, 2019 - link

    "thousands of units"?

    That does not sound like much.
  • TheinsanegamerN - Monday, December 23, 2019 - link

    It's a sample. You done see more then a few thousand ES intel chips per generation.
  • azfacea - Monday, December 23, 2019 - link

    "As a result, only select companies – who happen to run software that considers peculiarities of SMR and a lower per-TB IOPS – are expected to use Western Digital’s 20 TB SMR drives"

    is it worth throwing that much software engineering man-hours to save a few pennies on so called cheaper storage? and what do these little microwave ovens do to heat management and data center TCO? HDD are at a point where they take half a step fwd after 5 years and 3 steps back

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