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Apple's New Fusion Drive Works on Older Macs
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OK, this has been said in various ways already but I'm hoping to make it a little clearer.
Macs have the capability of creating a logical dive out of several physical drives (i.e. RAID) and the capability of creating multiple logical drives out of one physical drive (partitioning)
What is new is that in addition to being able to create a RAID logical drive, you can now create a Fusion logical drive. Apple want to sell you a physical drive that has both the components needed in a single physical drive (hybrid). What this guy did was figure out that you can build your own physical drive (in this case an internal SSD and a USB HDD) and OS X will treat it the same as if it were a purchased hybrid drive.
So Apple is not selling any "Fusion Drives", they are selling hybrid drives that will be recognized as logical fusion drives.
So the article is correct because he did create a "fusion drive" which is a logical drive created in OS X that uses a combination of an SSD and a HDD. Now what will be interesting is to see if someone can actually do this with a hybrid drive. This may be more difficult since there is a single controller in the drive and to make a fusion drive as this fellow has done you really need two controllers that OS X can access to determine what is the SSD part and what is the HDD part. But, maybe someone smarter than me will figure it out.
Macs have the capability of creating a logical dive out of several physical drives (i.e. RAID) and the capability of creating multiple logical drives out of one physical drive (partitioning)
What is new is that in addition to being able to create a RAID logical drive, you can now create a Fusion logical drive. Apple want to sell you a physical drive that has both the components needed in a single physical drive (hybrid). What this guy did was figure out that you can build your own physical drive (in this case an internal SSD and a USB HDD) and OS X will treat it the same as if it were a purchased hybrid drive.
So Apple is not selling any "Fusion Drives", they are selling hybrid drives that will be recognized as logical fusion drives.
So the article is correct because he did create a "fusion drive" which is a logical drive created in OS X that uses a combination of an SSD and a HDD. Now what will be interesting is to see if someone can actually do this with a hybrid drive. This may be more difficult since there is a single controller in the drive and to make a fusion drive as this fellow has done you really need two controllers that OS X can access to determine what is the SSD part and what is the HDD part. But, maybe someone smarter than me will figure it out.
I think all signs point to this basically being the same thing as Fusion Drive. It's already built into OS 10.8 (10.7.4 even), and from the announcement it appeared to be a software implementation.
No one will of course know for sure until these iMacs are in the wild, but these hacked versions seem to do exactly what Apple was promising in the presentation.
No one will of course know for sure until these iMacs are in the wild, but these hacked versions seem to do exactly what Apple was promising in the presentation.
but useless to me. Please explain to me why I'm paying £99 more for a new iMac, which lacks an optical drive, has no user upgradable ram, no firewire port, the SD card slot is now on the back an annoyance, a much slower 5400RPM hard drive, the old ones where 7200 RPM all for the sake of thinness?
An optical drive is crucial to me in a busy month as I must burn 20-30 DVD's I shoot weddings etc. This iMac flies compared to my old '09 MacBook Pro, its shocking to see how slow Aperture actually was on it.
Its a desktop why does the new iMac need to be this thin? Way too much compromise for me. I'm so glad I settled for the last gen, I'm willing to bet that my stock basic 2011 iMac will easily beat the new basic end iMac at pretty much all tasks, especially the stuff I do. A laptop 5400RPM drive has laughable performance editing RAW files in Aperture from a DSLR, no matter how fast the CPU.
That 100 quid I would have wasted has gone straight towards my rowers one piece for Uni
and also 32GB RAM for it in the near future xD
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To answer the question about boot camp, boot camp can't run on a fusion drive. To use boot camp you make a logical partition (subdivide a physical drive) to make a drive that Windows can read. So, if you used an Apple purchased hybrid drive that was being used as a fusion drive, you would have to create a logical Windows partition on the drive which would reduce the size of the fusion drive. When you boot into Widows it would use that portion of the HDD and ignore the SSD and the rest of the HDD that was part of the fusion drive.
I don't think that this part is true. In the presentation of the new iMac, the hard drive and SSD were in different physical locations. Most hybrid drives don't have nearly the storage capacity of the SSD part in Fusion Drive, it would make much more sense for Apple to implement a software solution that uses 2 standard drives. Especially since there are iMac models that only have 1 or the other.
It is a single HFS+ Volume entity. From the user perspective, it doesn't matter. It is used as one drive.
For better or worse the primary thing that Apple is doing is not trying to turn "Fusion Drive" into some low level geeky description of the implementation. They are just describing the benefits and end user experience. That shouldn't be surprising for an Apple product.
On the technical level is is both a cache and a nonstandard RAID implementation. None of that particularly matters if it "just works".
I know the chances of an "FusionDrive" app making it into the store is a long shot. But a third party could make an app to handle the command-line stuff, yes?
Combine SSD with hybrid HDD for even better performance?
Ok, so if we can "roll our own" Fusion drive, we should be able to use a hybrid HDD in place of a standard HDD, since it appears like a standard HDD to the OS, right?
If so, that should result in even better performance, correct?
Ok, so if we can "roll our own" Fusion drive, we should be able to use a hybrid HDD in place of a standard HDD, since it appears like a standard HDD to the OS, right?
If so, that should result in even better performance, correct?
Wow. You started off pretty good, but then made it clear as mud when you inserted hybrid drives into the conversation. Fusion Drive has nothing to do with hybrid drives and Apple is not selling hybrid drives. Fusion Drive is simply an SSD drive and an HDD drive joined together as a single logical volume; or 2 physical drives as one logical volume, similar to RAID. The developer did not "build your own physical drive" and new Fusion Drive Macs do not contain a "purchased hybrid drive".
To sum up, Fusion Drive DOES NOT EQUAL existing hybrid drive tech. It is a consumer level implementation of enterprise server auto-tiering.
Should be pretty elementary. The main work involved is anticipating possible problems and testing to make sure it works reliably on 99.999% of Macs.
As I have thought about this more, I'm betting that Apple is not installing hybrid drives at all in the new iMacs. The most likely scenario is that they are soldering SSD memory in and putting a separate HDD and creating a logical hybrid drive using the two separate controllers. When iFixit does the teardown, I'll be proven right or wrong.
Edit: tipp and madmax caught my error while I was typing this.
Edit: tipp and madmax caught my error while I was typing this.
It is known that there are 2 different physical locations for the HDD and SSD (I posted the diagram above), plus the iMacs can be configured with 1 or the other, or both. All signs point to 2 separate drives with separate controllers.
Possibly, but there might be diminishing returns having two levels of controllers trying to optimize by moving data around. It shouldn't hurt anything, because like you said, hybrid drives appear to the OS as a normal drive and the optimization routines happen on the drive's controller, but the data stored on the HDD is the less used data anyway, so this is unlikely to provide any significant increase in performance
I don't think it would hurt it, but the benefits might be questionable. They are operating independently at 2 different levels, one (Fusion Drive) is basically superceding the benefits of the other.
If that's the HDD you already had, then no worries I bet. But most likely not worth the extra expense of getting a hybrid drive over regular HDD.
Apple would probably deny it on the basis of "duplicating existing functionality."
If you mean "hybrid drive" like the Seagate Momentus XT HDD, then you are correct - they are not.
Apple themselves showed us how they are implementing it:
- A "blade SSD" like those used on the MacBook Airs and MacBook Pros with Retina Displays.
- A standard 2.5" or 3.5" (depending on the model of Mac Mini/iMac) laptop/desktop hard disk drive.
These two physical disk drives are then combined into one logical disk drive via the "Fusion" software and that one logical disk drive is then presented to the OS | Apps | Data.
I remember reading something about the files moving after the application is closed, so the "file moving" that could slow your work down is done later.
But I wont argue against a system that works for someone else...... I just want something that integrates a midsize SSD, a big HDD and also allows for TimeMachine. All that plus I dont want to have to fiddle with it, It Just Works
There's nothing to bet. Apple has stated that there is a separate SSD and HDD. The only question is the form factor the SSD takes, and so far, it looks like it's similar to the NAND flash modules in the MacBook Airs and Retina MacBook Pros. Still, there shouldn't be any reason why it wouldn't work with a standard SSD.
This should mean that the method described could potentially be stable since it should be virtually what Apple is doing. I have a Hackintosh that I use for just this kind of tinkering but I have held off on the SSD because I didn't want to screw around with files spread across several drives. But, now I may get one and try this method since it would be invisible to me in use, but would also really speed things up.
Given the class of storage drives that already have the hybrid label that is a no. Hybrid car is not two cars. It is one car that is "both". Hybrid mule is not two animals ( a horse and a donkey). It is one animal that is "both".
While you could stretch the logical volume provided by CoreStorage as being a hybrid logical volume. However, it would be stretch to overlap that notion in the same world were there are single entity SDD/HDD hybrid drives.
Apple uses Fusion as being different from hybrid in part because what they've done is different from what is already out there.
P.S. Physical hybrid drives suffer from usually having too small a SSD to be effective in a broad range of contexts. The "cache" size is just too small relative to the HDD storage component. That is in part driven by largely only targeting 2.5" drives at first. There isn't much empty space inside of a 2.5" drive to work with. The same space means have to do heavy writing to a limited number of flash memory modules. that usually tiggers using much more expensive SLC flash instead of mainstream MLC flash.
If Apple uses a 128GB drive with a 1TB HDD about 10% of used capacity can be on the SDD ( assuming don't fill the system to the brim. Shouldn't for a variety of reasons ). 2.5" hybird drives typically have 4GB and either capacities in the 500GB 1,000GB range. That means in the 4% range.
It is much easier to get a good sized working set in 10% than it is 4%.
Oye. No reading of the article or any comments, eh?
Read up here:
http://www.anandtech.com/show/6406/understanding-apples-fusion-drive
nice
can we use USB 3 and have the SSD as an external drive?
That would be a problem. The operating system assumes (quite reasonably) that any partition is either there and up and running, or it is not there. With that setup, you would have a partition that is half on your internal drive and half on the external SSD, so if you remove the SSD, you now have a partition that is only half there. That's asking for trouble.