In a move I honestly never thought would happen, Seagate is announcing today plans to brings its 5mm 2.5" Laptop Ultrathin HDD to Android tablets. The drive will come as a part of Seagate's mobile enablement kit and offered to OEMs looking to cost effectively scale tablet storage beyond what's realisticaly possible with NAND alone.

Seagate's reference design still includes a small amount of NAND (8GB) on the tablet in addition to the 500GB Ultra Mobile HDD. The HDD itself has been modified to include an additional gravity sensor, making the drive a bit more robust as the physical usage model with a tablet can be a bit more intense than a traditional notebook. The mobile enablement kit also includes Seagate's Dynamic Data Driver for Android, effectively an SSD caching layer. The combination of NAND flash and Ultra Mobile HDD will present themselves to the user as a single volume, with the Dynamic Data Driver choosing what data to keep on NAND and what to keep on the HDD. The driver also communicates sensor data from the tablet to the HDD itself, allowing it to better prepare itself in the case of a drop.

One of the reasons for the current success of modern day tablets and smartphones is because they don't rely on mechanical storage, which can deliver a poor user experience for random (or pseudo-random) accesses that are common in client workloads. As is the case with all NAND caching solutions, success is  really a matter of the OEM putting enough NAND on board to effectively cache everything but large media transfers. In the PC space, we don't see a lot of that, but in tablets where the amount of NAND you need is pretty small to begin with I feel like there's more of a chance of this not being horrible. Peak sequential performance from the Ultra Mobile HDD is around 100MB/s, making it better than most eMMC solutions in tablets today. Random IO is obviously the problem, but a properly sized cache should help make sure most random requests are serviced by the NAND in the system.

There are other downsides of course. Although Seagate's Ultra Mobile HDD is only 5mm thick, it's still a 2.5" drive - which does eat up valuable real estate inside a tablet. Battery life can also be affected. Seagate claims no impact on battery life since the Dynamic Data Driver can spin the HDD down when it's not in use, but when the drive is in use you're looking at a power penalty of 500mW to 1.4W. That's about the range of power consumption (idle to web browsing) for the entire SoC in the 2013 Nexus 7.

Overall it's an interesting idea but one that I don't expect to gain tons of traction, at least not in traditional Android tablets. In convergence devices, maybe. Perhaps the bigger question here is: what does the future of mechanical storage look like in ultraportable client computers? Our recommendation for years now has been SSD + large HDD if you can fit them both, otherwise just an SSD + external/cloud storage. Do you guys see the market, particularly cost sensitive portions of it, evolving any differently?

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  • solipsism - Monday, September 9, 2013 - link

    Moving into 2014 this doesn't seem like a great solution for mass market tablets. NAND is already slow enough and battery life precise enough that it doesn't seem viable for anything other than a fringe usage case.

    I would much rather see a notebook PC paired with an SSD + 2.5" single-platter HDD. For example, IMO the Retina MBPs would be much better machines that are still fast and have plenty of battery life if they added a Fusion Drive (single-platter HDD + PCIe SSD).
  • nerd1 - Monday, September 9, 2013 - link

    Most windows laptops provide empty mSATA slots so they can be easily configured as SSD+HDD combo. Obviously apple does not allow that.
  • ET - Monday, September 9, 2013 - link

    It's an interesting idea, in particular as a second drive for Windows tablets, and may be okay for 10" tablets and larger. It might work for smaller ones if the disk was 1.8" and lower power.

    All in all, I can see a market for this. Any tablet aimed at being usable as a full PC would need a decent amount of storage, and even a 1.8" drive should be able to provide 250GB at least. If the price is low enough, that would be a good upgrade to the specs.
  • solipsism - Monday, September 9, 2013 - link

    ET wrote, "Any tablet aimed at being usable as a full PC would need a decent amount of storage…"

    I'm not seeing much, if any of that with tablets. The "pro" users that have tablets (e.g.: users that read this site) are likely not replacing any standard PC by incorporating a tablet, but the users who are replacing their PC completely with a tablet device are users that never needed much power, performance, or storage capacity to begin with.
  • ET - Tuesday, September 10, 2013 - link

    It's a young market still. The options are just not there. But most people did switch from desktops to laptops, and going the tablet/phone way is a natural progression. Having all your programs and data on you everywhere you go, and being able to connect that phone/tablet to a screen and keyboard to work or to a TV and controller to play is a natural way of consolidating your computing devices into one. It's not there yet, but I see it as the way forward.
  • ET - Tuesday, September 10, 2013 - link

    Oh, and by the way, a lot of mobile users do want lots of storage. Maybe not all of them, but even my Nexus 7's 32GB is mostly full just installing games. If I was watching movies on it, or taking pictures / videos (which is not possible with the original Nexus 7 I have, but in concept), I'm sure I'd have run into a storage problem already. Given more storage as standard I'm sure mobile games would take advantage of it.
  • lmcd - Monday, September 9, 2013 - link

    This is brilliant, because mobile is right now optimized to fit in 8GB anyway. The only things that should end up on the HDD are active-use items, not passive-use items, so the idle penalty will be small.
  • MarcusMo - Monday, September 9, 2013 - link

    I don't really see the point in large storage in mobile devices in the first place. To me all media consumption will be streamed to the device (netflix, spotify etc). If you remove the media, what else is there to store? Huge apps? To me, 32 GB on device storage is more than enough.
    Granted, you're not connected to the net all the time, but for those occasions you could easily do a local cache of a movie or two on your device, to last through a flight for instance. The point is that your media library will not exist on your device in the future.

    Everyone is not like me of course, and there's always someone with a huge stack of DVD:s somewhere that just have to get them onto their tablet. But even to these people, I don't see mechanical storage making sense for the following reasons:
    - The storage density is worse than NAND, and that gap will increase even more so when we get stacked NAND and further process shrinks.
    - The physical packaging limits the mechanical drive to a very specific size (after all, its a spinning platter).
    Those two factors will see a larger part of your precious internal real estate being occupied by the storage subsystem when compared to an ssd. Essentially this will leave device manufacturers with the choice between smaller battery or bulkier design. I don't see the first one happening, although for niche products, the second one might be viable. Wouldn't be too surprised to see Archos or someone with roots in the portable video player market releasing a bulkier media tablet based on this drive
  • garadante - Monday, September 9, 2013 - link

    For the people criticizing the longevity and durability of these potential drives, you're forgetting that mechanical drives have long been used in portable electronic devices.

    For my own personal anecdote, I've been using a 160 GB iPod Classic for years (and it's still the only Apple device I genuinely like and don't consider overpriced, overhyped toys). I believe the iPod Classic has been using 1.8" HDDs during it's entire, not inconsiderable lifespan. MP3 players are subject to the same harsh environments that any smartphone would be subjected to and likely much harsher than most tablets, and barring any seriously negligent damage, isn't really a weak link. I'd imagine the scenarios that would break the mechanical drive are similar or even rarer than scenarios which crack/break tablet and smartphone screens.

    It'll be a considerably long time before non-volatile flash memory can compete with mechanical storage in terms of both density -and- economy. Until then, I think mechanical drives with proper SSD caching are the best thing the market could do, from a practical and technical standpoint. But we all know these smartphone and tablet companies ~love~ being able to charge $100+ for an extra 16-32 GB of extra storage which only cost them a matter of dollars in NAND.
  • smartthanyou - Monday, September 9, 2013 - link

    One of the reasons for the current success of modern day tablets and smartphones is because they don't rely on mechanical storage, which can deliver a poor user experience for random (or pseudo-random) accesses that are common in client workloads

    LOL, no, that has never been one of the reasons that those devices became successful.

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