Two-Dimensional Magnetic Recording Due in 2017

Two-dimensional magnetic recording (TDMR) is a yet another technology that should help to increase areal density and this is something that Seagate is investing in. The manufacturer believes that TDMR helps to increase areal density by 5% to 10%. Plans were announced several months ago and during the conversation with Mark Re, it was confirmed that Seagate was on track to release its first commercial TDMR-based HDDs in 2017.

TDMR technology enables makers of hard drives to increase the areal density of HDD platters by making tracks narrower and pitches even smaller than they are today. While it is possible to minimize the writer (a part of an HDD's head that writes data), reading becomes a challenge. As magnetic tracks become narrower, they start to affect each other, an effect called magnetic inter-track interference (ITI). This means It becomes increasingly hard for HDD heads (readers) to perform read operations. To mitigate the ITI effect of very narrow tracks, two-dimensional magnetic recording technology uses an array of heads to read data from either one, or several nearby tracks (a method described in several scientific publications). This improves the signal-to-noise ratio delivered to the controller. Several readers enable HDD controllers to determine the correct data based on input from several locations, which implies the need for powerful controllers. More importantly, a number of read heads will be a benefit for HDDs featuring HAMR in the future: heat-assisted recording improves the write process, whereas multiple readers improve the read process. We are also told that with relevant programming, hard drives featuring an array of readers per head can increase the performance of HDDs. This will clearly not make the new hard drives as fast as SSDs, but it will help Seagate’s customers (particularly in the SAS space) to increase the performance of their storage devices. Right now, Seagate does not talk about its plans to use multiple readers in commercial drives because such products are several years out, but considers this a possibility.

Seagate confirmed that TDMR lets HDD makers to increase areal density by up to 10%, which is a noticeable amount compared to typical PMR platters. However, additional capacity does not come free in this case when it comes to computing. An array of heads increases bandwidth requirements for the controller as well as the amount of information that the chip needs to process. As a result, the whole TDMR platform becomes generally expensive: it features multiple arrays of heads, new platters, new motors as well as new controllers. This is why Seagate plans to use it for server applications first sometime in early 2017. Seagate did not confirm whether such HDDs would use both TDMR and helium, but said that virtually all technologies could be mixed and matched to build the right solution for every possible application. Keep in mind that these are plans which are subject to change.

Helium Will Remain Exclusive for High-Capacity Applications, For Now New 10K and 15K RPM HDDs Incoming
POST A COMMENT

91 Comments

View All Comments

  • Zak - Wednesday, July 6, 2016 - link

    Forget enterprise. I use 4GB drives as local backups and planning to go up to 6 or 8. Show me affordable 8TB SSD I can use for backup. Reply
  • inighthawki - Wednesday, July 6, 2016 - link

    8TB no, but I'm sure I can find you a few good 4GB drives :) Reply
  • cm2187 - Wednesday, July 6, 2016 - link

    WD Reds? Reply
  • cm2187 - Wednesday, July 6, 2016 - link

    Actually even cheaper if it is for backups: seagate 8tb archive drives. Reply
  • Samus - Wednesday, July 6, 2016 - link

    First off, GREAT article Anton. This is what AT is all about.

    I don't have a single HDD in my house anymore. Between 11TB on AWS and 800GB in OneDrive, it all comes down to the data centers which will all be using this technology.

    Meanwhile the 480GB SSD's that cost $100 running my PC's and laptop have made magnetic storage irrelevant for my consumer use, so who can blame Seagate for not targeting me?
    Reply
  • trivor - Thursday, July 7, 2016 - link

    What everyone seems to be missing it NASes for the home with LARGE MEDIA collections. When you're looking at 2 GB for DVD rips and 4-5 GB for Blu Ray rips you need Terabytes of storage for $30/terabyte (or less hopefully) that SSDs can't touch. Even for full Blu Ray rips (some people want this) you're still looking at only needing 50 Mbps without any compression and even a lossless rip with Makemkv will take it down to 20 GB and will easily stream from a NAS with any decent spinning drive. When SSDs which are currently around $200/GB (for a consumer commercially available drive) to compete with spinning drives (say 3 TB @ $94 for a Toshiba or 3 TB for WD Red @ $109) then we won't see much in the consumer space. Not to even talk about 8 TB drives for around $200-$250. We are a long way from the demise of consumer spinning drives. Reply
  • CaedenV - Thursday, July 7, 2016 - link

    No kidding! I love my SSDs, but they are not going in my Nas any time soon. I have 5 3tb drives in a raid 6...that would cost a mint in SSDs still. Maybe I'll get there eventually, but it is going to be a long time.

    Still, it is a sin to sell a pc with a hdd as a system drive these days. Really wish manufacturers would stop that
    Reply
  • JlHADJOE - Wednesday, July 6, 2016 - link

    IBM showed us that magnetic storage can store a bit using as few as 12 atoms. That's far denser than any type of memory developed so far.

    http://www.wired.com/2012/01/ibm-scientists/

    SSDs will replace HDDs for most of the consumer market, but HDDs will stay around for bulk data.
    Reply
  • Cygni - Wednesday, July 6, 2016 - link

    It's 'ogre'? Is shrek around or something?

    Also if you read the article, you will see that this isn't exactly focused at the same market as enthusiast SSDs.
    Reply
  • Michael Bay - Wednesday, July 6, 2016 - link

    Tell that to 8Tb of media I have copying to the new HDD now. Reply

Log in

Don't have an account? Sign up now