Apple’s new patented Fusion Drive is more advanced than you might think

“No one heard a peep in the last few months about Apple’s new Fusion Drive, a combination solid state and platter based hard drive that ‘fuses’ the best aspects of flash and traditional hard drive storage,” John Brownlee reports for Cult of Mac.

“Those aspects? Solid state drives (or SSDs) over much faster reading and write speed, as well as “instant-on” boot up from sleep or power down. This leads to huge performance boosts all across the Mac. Traditional hard drives, however, have a couple key advantages: they are both cheaper and have more capacity, allowing you to easily store massive media libraries,” Brownlee reports. “So what’s the point of the Fusion Drive? Simple. It’s the best of both worlds: the speed and instant-on of an SSD, with all of the storage space of an HDD. But how does it work?””

Lee Hutchinson explains for Ars Technica, “Apple’s Fusion Drive does not appear to function like an SSD-backed disk cache, but rather seems more like a file-level implementation of a feature that has existed for some time in big enterprise disk arrays: automatic tiering.”

“Most big disk arrays have different types of storage—some slow spinning disk, some faster spinning disk, and some solid state storage—and some have the ability to monitor what data is being accessed the most and can automatically move that data to a faster tier of disk as needed. These features typically operate at the block level, below the files, and can be done on large or small chunks of data, depending on what’s hot and what’s not,” Hutchinson writes. “Auto-tiering also includes the ability to take data that is no longer in demand, or no longer “hot” and demote it down off of fast disk and onto slower stuff. In this way, a file that doesn’t get accessed very often might be stored on slow SATA disks, but if a hundred people need to open it repeatedly over a short period of time, it will get pulled up and kept on SSD until it’s not needed anymore.”

Read more in the full article here.

Apple’s new Fusion Drive “fulfills a 2011 patent application,” Jack Purcher reports for Patently Apple. “On September 29, 2011 we posted a report titled ‘Apple is working a new Hybrid Drive System of their Own,’ and today Apple’s ‘887 patent application was fulfilled with the introduction of the Fusion Drive.”

“Fusion Drive automatically and intelligently manages your data so that frequently used apps, documents, photos, and other files stay on the faster flash storage, while infrequently used items move to the hard drive,” Purcher reports. “You’ll enjoy shorter boot times, and as the system learns how you work, you’ll experience faster application launches and quicker file access.”

Read more in the full article here.


  1. I wonder how the fusion drive handles highly demanding disk-intensive tasks like video rendering or encoding which are basically creating new files on the fly but benefit greatly by running on SSD vs. HD… Hopefully part of the intelligence built into OS X and the fusion drive would move on-demand disk-intensive tasks to the SSD portion of the drive as well as files which are frequently used.

  2. been there, done that. Sounds like a hybrid drive. While faster than a traditional HD, still slower than a SSD, I found having the OS and programs on the SSD, and data on a 10,000RPM secondary HD (for space) is a better way to go. Or 2 to 3 SSD’s.

    1. Uh, It’s not a hybrid drive. Hybrid drives were for cache only. It’s two drives in the iMac which they’ve offered for a while now. Fusion just makes the two drives show as one and the software moves your data to the SSD if you use it a lot.

      1. OK, well…we will see if the speed is comparable to a OWC Mercury Pro SSD. That is what I use in my 2009 MBP now, and it is so damn fast. For storage on my 2011 Mini, I use a buffalo mini station 1TB thunderbolt external. And that also is fast…hehe

        1. If you watch the presentation, Apple admits that it’s not as fast as an SSD-only solution. Their benchmarks show significant improvement over a HDD, and slightly slower speeds compared to SSD.

      2. No its a hybrid drive. OCZ has been producing drives very similar to this one for the last couple of years. OCZ was the first to put out a 128 gig SSD side iirc.

        I’m sure Apple has built their firmware to handle things how they best see fit but there is no plausible reason not to go with the hybrid hardware design, its compact and proven at this point.

        1. No ti’s not a hybrid drive. Hybrid drives don’t know anything about filesystems. They Just cache frequently used data on the flash drive. This (appears to) do more than that, it works at the filesystem level, not at the drive level.

    2. advanced hybrid drive. Alleviate some confusion that way. Yes, it is, in essence, a hybrid drive. With a significantly larger SSD segment and better software for balancing what is stored on which side.
      Minor in terms of “innovation”, perhaps, but significant in terms of speed.

  3. Makes me curious.

    What if I were to add a SSD inside my two year old 27″ iMac, alongside the existing 1TB drive … would a future OS X upgrade allow me to fuse these together?

    1. So, this sounds more and more like a software-based feature that uses TWO physical drives that appears as one very fast AND very large volume to the user. It is NOT a special “hybrid” drive mechanism.

      While listening to presentation, Phil Schiller actually describes Fusion Drive clearly (starting at about the 34 minute point). He says:

      “First, it’s 128 GBs of flash storage. Added to that… your choice, either one or three TB hard drive. In software, they are fused together into one logical volume…”

      Because of this software-based implementation, I think it can be applied very flexibly going forward. In my opinion, it should be possible to make it work in a Mac Pro, where you can have up to four internal drives, if one of them is a flash-based drive. I think it would also work in older iMacs with the built-in (from the factory) capacity to have both a hard drive and flash drive internally. Apple may (officially) prevent it from working with “after-market” solutions.

      If makes sense that this feature is restricted to only the new iMac and Mac mini initially, because that allows Apple to roll it out to a limited audience with precisely known hardware specs. Maybe for the next full release of Mac OS X, they will roll Fusion Drive out to a larger set of supported configurations.

  4. Any idea of what Apple’s charging for these? I’ve seen zero intro in all of the press releases and articles, and the BTO option isn’t available yet so the store site won’t tell me…

      1. I don’t think you get it.

        It’s not a piece of hardware. It’s a solution that integrates hardware and filesystem. You won’t be able to just buy one and attach it to your laptop, or replace a drive with a cheaper model from OWC.

  5. Haha!–to those out there that believe Apple no longer innovates. Per the title of this article, this IS more than one might think. I can see this Fusion Drive becoming very popular.

    But, get ready for Samsung to start their pirating motors.

  6. How does it handle wiping? The lack of vendor info about Secure Erase or cryptographic erase capability is a reason the hybrids may not be viable solutions in environments where security is a consideration. I hope this will be different.

  7. “best of both worlds” also comes with the problem: worst of both worlds comes along for the ride, plus the price and complexity that the customer can’t appreciate.

    Why didn’t Apple simply use its hoard of cash to lock in preferred pricing on as many SSD’s as Apple can get its hands on? Pass on a little of the savings to consumers and everyone would be happy. It would be the faster simpler solution.

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