selfmade fusion drive in iMac 2011 - "real" smart file management?

[lars666]

Hello everybody,

I am thinking about manually creating a fusion drive out of my 256 GB Apple SSD and 2 TB HDD inside my mid-2011 iMac, using one of the many instructions on the Internet. My only concern is: Will such a "selfmade" fusion drive (on an officially not supported older Mac) really work like the real one, meaning: managing the files the smart way, copying the ones used often to the fast SSD and the ones used rarely to the slower HDD? Or will the system just combine both drives to one big one, fill the SSD first and after that the HDD and that's it? I'm really interested in creating the "Fusion Drive" on my older drive, but only in the sense described first, otherwise I'll keep it this way ...

Anybody has a definite answer to that? Thanks a lot in advance for the help!!!

 

[Charcoalwerks]

I asked a similar question in another thread and "flopticalcube" replied...

Nothing special about the install. Once the hardware is in, its strictly a software choice as to whether you want a fusion drive or OS drive and data drive. No need to lose the SD reader.

He seems to really know his ***** when it comes to iMacs.

 

[Truthfulie]

Hello everybody,

I am thinking about manually creating a fusion drive out of my 256 GB Apple SSD and 2 TB HDD inside my mid-2011 iMac, using one of the many instructions on the Internet. My only concern is: Will such a "selfmade" fusion drive (on an officially not supported older Mac) really work like the real one, meaning: managing the files the smart way, copying the ones used often to the fast SSD and the ones used rarely to the slower HDD? Or will the system just combine both drives to one big one, fill the SSD first and after that the HDD and that's it? I'm really interested in creating the "Fusion Drive" on my older drive, but only in the sense described first, otherwise I'll keep it this way ...

Anybody has a definite answer to that? Thanks a lot in advance for the help!!!

DIY Fusion is just like the Apple made Fusion. You will not need to concern yourself with file management.

 

[flopticalcube]

Fusion is software. The underlying hardware is exactly the same whether its Apple or DIY. The only significant hardware difference is that on new iMacs, the SSD uses faster PCIe rather than SATA III but the difference is not really noticable in day-to-day use.

EDIT: I just realised you wanted to know the mechanism of Fusion. Its another term for "tiered storage". Most frequently read data is kept on the SSD and least is kept on the HDD. It appears to the system as a single drive. A part of the SSD is used for write cacheing. The whole thing is managed during idle periods.

 

[lars666]

Thanks for the answers. In this case, the Mac OSX software handles my "handmade" Fusion Drive exactly the same intelligent way. Great to hear. Thanks again!

 

[shoulin333]

I have a 2011 27" iMac. I added a 250GB Samsung EVO drive underneath the optical drive and set-up a custom fusion drive between that and the stock 1TB hard drive. It is totally hands off, things you access frequently are crazy fast.

You can tell when you stop using a program for a long while and then come back to it, it can be "slow" and you can hear it's data being read of the hard drive. After using that app regularly again maybe 3 or 4 times it speeds up as it is moved back to the SSD. The bigger the SSD you get the better overall experience you can have.

It is worth the work of taking the whole iMac apart to plug in the sata/power wire!

 

[lars666]

It is worth the work of taking the whole iMac apart to plug in the sata/power wire!

I don't even have to as my configuration already includes a SSD and HDD – so I think I definitely should try it out ... Thanks for the answer!

 

[Truthfulie]

I have a 2011 27" iMac. I added a 250GB Samsung EVO drive underneath the optical drive and set-up a custom fusion drive between that and the stock 1TB hard drive. It is totally hands off, things you access frequently are crazy fast.

You can tell when you stop using a program for a long while and then come back to it, it can be "slow" and you can hear it's data being read of the hard drive. After using that app regularly again maybe 3 or 4 times it speeds up as it is moved back to the SSD. The bigger the SSD you get the better overall experience you can have.

It is worth the work of taking the whole iMac apart to plug in the sata/power wire!

Do you have more than 250GB of Application data? I was under the impression that applications are always written on SSD portion unless you run of of SSD space.

 

[shoulin333]

Do you have more than 250GB of Application data? I was under the impression that applications are always written on SSD portion unless you run of of SSD space.

I think this is because I do a lot of .NET programming under a Virtual Box VM. I believe the VM virtual hard drive file is treated as one giant application file. So because of this if I use the VM a ton then it sort of takes over the SSD and say Numbers or Excel for mac can get pushed over. This probably wouldn't be the case if all my apps were OSX based without the VM... or I had a bigger SSD. Good catch, I hadn't actually thought about that....