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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  • jordanclock - Monday, December 23, 2019 - link

    It is absolutely worth it when you are dealing with high re-write data usage. The core product of the company I work for would chew up SSDs entirely too quickly, especially since there would be almost no performance benefit. We need an absolute ton of storage that can survive a lot of writes and much lower reads (most of the reads are from re-writing data) and HDDs are still king for that.
  • Santoval - Wednesday, December 25, 2019 - link

    "..HDDs are still king for that."
    That is not going to change if NAND vendors continue to fatten the NAND cells. We are already at QLC and there is (crazy) talk for even more bits per cell than that. On the other hand there is the opposite trend in the market for high endurance along with quite higher performance, but at lower capacities. I am talking about Samsung's Z-NAND and Toshiba's XL-FLASH (both in SLC mode at first), and of course Intel/Micron's 3D XPoint.

    The first two are largely equivalent in performance, capacity range and endurance. Performance will probably be somewhat higher than old style SLC NAND, the capacity will be up to ~1 TB (for the SLC based ones of the first generation) and the endurance will be roughly 10 DWPD (Drive Writes Per Day) for 5 years. SSDs with 3D XPoint have a similar capacity, a bit higher performance and the second generation of SSDs has an outstanding endurance of 60 DWPD for 5 years, which competes in endurance with the average spinning rust.

    The problem? Due to their very high cost per GB all three are targeted at the enterprise market (with the exception of tiny SSDs intended as cache for HDDs). Consumers and small businesses will need to make do with TLC and crappy QLC+ based SSDs...
  • SaberKOG91 - Monday, December 23, 2019 - link

    SMR is an excellent replacement for Tape in a lot of environments. It has good sequential throughput which is useful for backups and other large file storage. The densities are also still much better than SSD in $/GB. As for the heating elements they are very small and do not affect the heat produced by the drive by enough for it to matter. Most of the heat in any HDD is the motor and anything these new heads use is negligible.
  • cbm80 - Tuesday, December 24, 2019 - link

    Even ignoring R&D, I don't think it saves money. The reason is you can sell CMR drives for good money to used-drive marketers when they reach the end of their life as a data center drive, but SMR drives will be worthless.
  • TheinsanegamerN - Monday, December 23, 2019 - link

    Given how big games ahve gotten, you'll need at least one of these in your steam machine in the next 5 years.
  • Achaios - Monday, December 23, 2019 - link

    ? I don't think so.

    I checked Steam and I only have 7 games. You know what? Of those 7 games I own, I only have installed Civ VI in my SSD, because that's the only one I am still playing.

    The remainder 6 STEAM games I own I simply uninstalled because I no longer play. If I ever get the urge to play one of them again, I will re-install them. Unthinkable, I know, huh?

    My Raid 1 of 2 6TB drives is about 40% full.

    At that rate of accumulating DATA in my HDD's, I will have probably passed away first before I ever need a 18TB or 20TB drive.
  • Ushio01 - Monday, December 23, 2019 - link

    Must be nice to not have to monitor monthly allowances.
  • inighthawki - Monday, December 23, 2019 - link

    A very large number of people do not possess internet that is fast enough to download games on the fly, or have data caps that can make it very difficult to swap between a lot of games in a month.

    Most people also play more than one game, and own more than seven.
  • rahvin - Thursday, December 26, 2019 - link

    With only 7 games in his Steam Library he's not a gamer and even responding to this thread about the need for Steam storage just demonstrates ignorance of that.
  • Railander - Monday, December 23, 2019 - link

    pretty sure that was a joke

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