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New Technique Promises Much Faster Hard Drive Write Speeds

Posted by Unknown on from the sharks-in-my-drives dept.

MrSeb writes "Hold onto your hats: Scientists at the University of York, England have completely rewritten the rules of magnetic storage (abstract; full paper paywalled). Instead of switching a magnetic region using a magnetic field (like a hard drive head), the researchers have managed to switch a ferrimagnetic nanoisland using a 60-femtosecond laser. Storing magnetic data using lasers is up to 1,000 times faster than writing to a conventional hard drive (we're talking about gigabytes or terabytes per second) — and the ferrimagnetic nanoislands that store the data are capable of storage densities that are some 15 times greater than existing hard drive platters. Unfortunately the York scientists only detailed writing data with lasers; there's no word on how to read it."

35 of 148 comments (clear)

  1. write only media FTW! by Anonymous Coward · · Score: 5, Funny

    Who needs to read data back anyway?

    1. Re:write only media FTW! by NoNonAlphaCharsHere · · Score: 4, Funny

      But that means we have to use Perl!

    2. Re:write only media FTW! by Robert+Zenz · · Score: 4, Funny

      Absolutely true! I store all customer user-accounts in /dev/null to save diskspace (the compression of that device is awesome!)...so far nobody complained.

    3. Re:write only media FTW! by The+MAZZTer · · Score: 5, Funny

      Let me guess... you set up customer complaints to get filed in /dev/null too?

    4. Re:write only media FTW! by greenreaper · · Score: 4, Funny

      No, but you have to login to file a complaint.

  2. So how do they know if they actually wrote it by Anonymous Coward · · Score: 2, Interesting

    If they can't read it, how do they know if they actually wrote it? Or maybe reading it is 10,000 times slower than current read technology.

    1. Re:So how do they know if they actually wrote it by TheRaven64 · · Score: 5, Informative

      It's stored in the same way as a normal hard disk - in ferromagnetic domains on a platter. You can still read it back using the same techniques as current drives (i.e. put a coil over it and see which way the induced current flows), but you then have a drive that you can write to orders of magnitude than you can read from it. I can think of a few places where this might be useful. The most obvious is the underlying storage for something like ZFS. For reliability, you want to flush everything to the backing store as quickly as possible, and with copy-on-write and snapshotting you may never erase it, but most of your reads are satisfied from flash or DRAM caches. A drive using this technology would let you dump data there as quickly as you wanted and would let you read it back for data recovery if you needed to, while in normal operation you wouldn't care about the read speed because reading from the disk is comparatively rare. It would also be useful for a number of scientific applications. I did some work a few years ago with someone building a solar observatory. A single one of their cameras generated 10GB/s of data, and they had 8 cameras in a typical setup. They run these for the entire time that the sun is visible. A single drive that can handle a sustained write speed of 1GB/s would be very useful for them (although they'd fill up several per hour...).

      For consumer devices, random read speed is still the most important factor, and mechanical drives suck at that.

      --
      I am TheRaven on Soylent News
    2. Re:So how do they know if they actually wrote it by Stonent1 · · Score: 3, Insightful

      I would think that you would still have to read the location of the cluster before writing to it. Sure you can flip magnetic particles N > S or S > N at bazillions per second speed but if you don't know what you're flipping that's not good.

    3. Re:So how do they know if they actually wrote it by the_B0fh · · Score: 3, Insightful

      Why? If they can write TB/s and store data at 15X of current capacity, and SSDs can't, why move to SSDs?

      The read problem is easily resolved by having multiple read heads that can read independently.

    4. Re:So how do they know if they actually wrote it by sheepe2004 · · Score: 5, Informative

      Nope, that was a few years ago. Now they use TMR http://en.wikipedia.org/wiki/Tunnel_magnetoresistance#Applications .

      --
      http://compsoc.man.ac.uk/~shep/
    5. Re:So how do they know if they actually wrote it by sheepe2004 · · Score: 2

      Because the actual research that has been done is fundamental physics. For better or worse news articles always talk up the applications rather than the science.

      --
      http://compsoc.man.ac.uk/~shep/
    6. Re:So how do they know if they actually wrote it by tibit · · Score: 4, Interesting

      It's time to dust off the old concept of hard sectored discs ;) Realistically, of course, it's a bit more complex than that.

      First of all, modern hard drives have a servo track that's used to maintain radial position of the head servo. Instead of each hard drive having a very accurate (and expensive) radial and axial head position sensor, you pay for it once, install it in the factory, use it to accurately guide a hard drive to write the servo track. Its cost is amortized over thousands of drives made. This is probably the reason for a covered up radial slot in many hard drive enclosures: I guess it's used for the sensor to couple with the head system while the drive writes the servo track. Or perhaps the servo platter is prewritten outside the disc? Someone familiar with how it's made please chip in!

      The servo track can be also used to provide angular position feedback. A rough estimate of angular position of the spindle is available first from the Hall sensors in the spindle motor. A somewhat more accurate estimate can be had from back-EMF from the spindle motor windings. This still is methinks a couple orders of magnitude away from what's needed to pack sectors tightly on the drive -- thus the feedback can come from the servo track. Not having to read the data tracks helps with packing the sectors: there's no read-write switchover overhead (if it were significant -- perhaps it isn't nowadays). The servo head is always reading, and the data heads can be kept in write/erase standby. It'd be nondestructive, but read amplifiers are disconnected to prevent saturating them -- amplifier overload recovery is slow. Heck, if you want an amp that recovers from overloads quickly, you have to split it into more stages, and you need fast clamps between each stage. There are other similar approaches to this problem, too, and perhaps modern read amps are designed to deal with overloads gracefully -- I never tested a recent one. Stuff from a decade ago was painfully slow on overloads (tried to reuse a head amp from a hard drive for a non-drive-related project).

      Alas, this ultra-fast-writing drive would unfortunately need very accurate position sensors -- both angular and radial. It's an engineering issue to make those affordable, as is the design of the optochip with femtosecond laser and its driver and serializer. The latter would probably take a couple serial lanes and multiplex them -- I presume it's not all that easy to push 10gbit/s data between external chips and the laser driver/laser combo. I think that to make it all practical you need an on-chip serializer, write precompensation, driver, and the diode. Perhaps the diode would be "tacked on" later to a substrate that has everything else. I only imagine that bond wire parasitics, even over a couple mm, become kinda important when the laser waveform has a 100GHz bandwidth...

      --
      A successful API design takes a mixture of software design and pedagogy.
    7. Re:So how do they know if they actually wrote it by mike260 · · Score: 2

      Was the magnetic write head ever the main bottleneck?

      Maybe not the 'main' bottleneck, but it depends on the application, no? Seems to me there are at least a few firehose situations where you can never have enough write bandwidth (say, uncompressed video-capture).

      Maybe normal workloads on normal filesystems wouldn't see much improvement, but I bet you could find ways to capitalise on the extra bandwidth and space. Log-structured filesystems spring to mind for one.

  3. At last! by undulato · · Score: 5, Funny

    A future-proof storage medium.

  4. omg by Anonymous Coward · · Score: 4, Funny

    frickin hard drives with laser beams!

    1. Re:omg by Ihmhi · · Score: 5, Funny

      1) Western Digital licenses this technology.

      2) WD releases a new model, the WD Shark. A "Now with LASERs!" starburst graphic adorns the front of the box.

      3) Profit!

      --
      Random Thoughts From A Diseased Mind (Not For Dummies)
    2. Re:omg by jones_supa · · Score: 2

      Sharks could also swim their way out of flooded manufacturing plants.

  5. Who cares about reading? by rjejr · · Score: 5, Insightful

    Considering how often I back stuff up, but how rarely I ever use those backups, I'll gladly take 1,000 times faster backups even if it means slower read speeds than we have now. Really, I'ld take that trade-off in a heartbeat.

    1. Re:Who cares about reading? by Anonymous Coward · · Score: 3, Insightful

      You can only write as fast as data can be read so your backups will not be 1,000 times faster.

  6. Promises, Promises by na1led · · Score: 2

    If I remember correctly, several years ago they said a 500 Terabyte Drive would be comming out soon, never happend.

    --
    -- By all means let's be open-minded, but not so open-minded that our brains drop out.
  7. Good news everyone! by Yvan256 · · Score: 3, Insightful

    If they can read it at least as fast as today's technologies, the power required to read/write data is roughly the same as today's drives and the manufacturing cost is also about the same, this is good news for everyone:

    1. On the consumer side, cheaper drives per terabyte meaning cheaper home media servers
    2. On the commercial side, a lot less energy required, i.e. no need for ultra-fast 15k RPM drives in servers, need up to 15 times fewer drives in server farms. This is BIG.

    There is only one problem.

    1. Re:Good news everyone! by HockeyPuck · · Score: 2

      We have 15k RPM drives because we need to move the sector to which we want to read/write at quicker to the actuator head. The slowest point isn't the transfer of data from head to platter, but a) moving the actuator arm and b) waiting for the correct sector to come around.

      I'm not sure how much performance benefit using lasers could help since access time (moving the mechanical arm) is still on the order of ms.

  8. Re:To read it, you say? by linuxgeek64 · · Score: 2

    Blu-Ray is an optical medium. Hard drives are magnetic. The use of lasers in writing is unusual. They use the lasers to flip magnetic bits. The lasers can't simply be shined onto a bit and then have light deflected in one of two directions depending on the data stored.

  9. Write without reading? by Synon · · Score: 3, Interesting

    "Unfortunately the York scientists only detailed writing data with lasers; there's no word on how to read it." A bit of a paradox don't you think? How did they know it was written without being able to read it?

    1. Re:Write without reading? by robot256 · · Score: 2

      Probably they used a scanning-tunneling electron microscope or similar to do the read. Those obviously don't scale down easily, hence there is no practical way to read the data yet.

  10. Re:Congratulations! by Walking+The+Walk · · Score: 2

    For writing, magneto-optical drives only used the laser to heat up a bit to a point where it could be flipped. The actual magnetic drive head flipped the heated bit, not the laser. This post says they can now use the laser to flip a bit, and that's a big difference.

    --
    A recursive sig
    Can impart wisdom and truth
    Call proc signature()
  11. Readback can be easier by goombah99 · · Score: 5, Interesting

    This solves a major problem with mag recording. Readback head have always been way smaller than write head. You can read back with just a tiny permalloy head but to write you need large currents and loops of wire. So miniaturization has been limited by the write head size not the read head. This solves the write-head size problem but may have created a new read head problem. But that's very promising.

    --
    Some drink at the fountain of knowledge. Others just gargle.
  12. Re:Now... by larys · · Score: 2

    Yeah, sure...it's all fun and good until word wrap is set but the window of Notepad isn't stretched to the right width and all of a sudden some otherwise beautiful woman is wearing her own breast as a hat...

  13. Cryogenic data storage by goombah99 · · Score: 3, Funny

    This is the data equivalent of freezing Walt Disney and assuming that someday we'll figure out how to thaw and revive him. Write now, read someday.

    --
    Some drink at the fountain of knowledge. Others just gargle.
    1. Re:Cryogenic data storage by jd2112 · · Score: 3, Funny

      His first words after being thawed out would be "is 'Stramboat Mickey' still under copyright?"

      --
      Any insufficiently advanced magic is indistinguishable from technology.
    2. Re:Cryogenic data storage by ProbablyJoe · · Score: 4, Insightful

      And the answer will almost certainly be yes.

    3. Re:Cryogenic data storage by BigSes · · Score: 5, Funny

      Walt: "Are all the Jews gone?" Scientist: "No." Walt: "Put me back in."

  14. No you can't by cnaumann · · Score: 2

    This uses ferrimagnetic domains, not ferromagnetic domains. There is no external magnetic field, and you can't use a coil to read them.

  15. Re:Memory Hole by GodfatherofSoul · · Score: 3, Funny

    Goatse Drive technology?

    --
    I swear to God...I swear to God! That is NOT how you treat your human!
  16. Comment removed by account_deleted · · Score: 2

    Comment removed based on user account deletion