New iMac 2012 - Should I create my own Fusion Drive?

[noob17]

Hi All,

So i finally took the plunge and ordered a non-fusion 27 imac 27". I do however have a lacie rugged ssd - thunderbolt which i was going to use as a primary drive and install the OS on there.

Then i came across the following which shows how to combine an ssd and standard HD into a fusion drive:

http://reviews.cnet.com/8301-13727_7-57550128-263/how-to-make-a-custom-corestorage-drive-in-os-x/

I am mainly going to use this computer for media (watching movies and browsing and the occasional office work).

Should i go through the hassle of creating the fusion drive? Or should i just stick to using the external ssd as the primary drive?

 

[Bear]

...
Should i go through the hassle of creating the fusion drive? Or should i just stick to using the external ssd as the primary drive?

If both drives are not in the same enclosure, I would recommend not making a fusion drive from them. If for some reason one of the drives loses power or connectivity while the system is in operation, that breaks the fusion drive and would entail some sort of recovery. If you're not lucky at all that recovery would entail a restore, although I suspect in most cases, it would just require some recovery operations.

 

[macthefork]

The Lacie Rugged is powered through the Thunderbolt connector so you probably shouldn't use a SSD greater than 256GB.

Before using the Terminal commands, you could try booting into the Recovery Partition (Command + R) to see if it will see the Thunderbolt Drive (external TB drives show up on the SATA buss when using Thunderbolt).

It may only look for Apple branded drives only so may not work. But, if it did, it would be the easier solution.

Under this kind of Fusion Drive (using an external SSD) I would be sure to maintain an up-to-date backup at all times.

 

[noob17]

stuck to booting from external ssd and using internal for a Time Machine backup of ssd and the rest of the internal HD for storage of media

 

[rkaufmann87]

stuck to booting from external ssd and using internal for a Time Machine backup of ssd and the rest of the internal HD for storage of media

Clever but do you really want to use the internal drive as a TM drive? Seems that if you lose a logic board or the internal HD crashes there there goes the backup. It sounds like it would be best to put TM on an external HD.

 

[Mike in Kansas]

If both drives are not in the same enclosure, I would recommend not making a fusion drive from them. If for some reason one of the drives loses power or connectivity while the system is in operation, that breaks the fusion drive and would entail some sort of recovery. If you're not lucky at all that recovery would entail a restore, although I suspect in most cases, it would just require some recovery operations.

It entails plugging the drive back in or turning the drive back on. I have been using a "roll your own" FD for 6 months. I fused my 240GB internal SSD with a 2TB external FW800 drive and it has been trouble free the entire time. If the external drive loses power or become unplugged, the system just hangs until the drive gets reconnected. I have pulled the drive while it was being written to, and no errors have occurred. It's a pretty robust set up.

 

[Fishrrman]

"Should i go through the hassle of creating the fusion drive? Or should i just stick to using the external ssd as the primary drive?"

The question to ask yourself is:
"Am I comfortable with managing two drives [instead of just one]?"

If your answer is "yes", stay as you are.

I recall seeing some speed comparisons posted.
On one side was just an SSD (no fusion setup).
On the other was a "fused" pair of drives (SSD + HDD).

The "regular" SSD (not fused) actually yielded speed results that were better.
The fusion setup approached SSD speeds, but didn't quite measure up.

Again, if there's nothing that bothers you about managing two drive icons on the desktop instead of one, leaving things as you are now may actually be the fastest.