Possible to boot from Lacie 1TB Thunderbolt SSD?

DerekS

macrumors 6502
Original poster
Jun 25, 2007
336
3
I'm unhappy with Fusion performance.

I've considered selling this (Late 2012) iMac and upgrading to one with straight SSD, but with new iMacs potentially around the corner that seems like a bad move.

I am considering the Lacie 1TB Thunderbolt SSD as a stopgap until we see new iMacs.

Is it possible to boot from software raid on an external disk?

I don't want to split the raid, that would halve the performance and defeat my goals.

I haven't been able to get a straight answer on this anywhere.
 

MacsRgr8

macrumors 604
Sep 8, 2002
7,832
1,126
The Netherlands
I'm not 100% sure, but I cannot see why not:
OS X can boot from an internal "soft"-RAID 0 (or RAID 1) built on 2 S-ATA HDDs and a Mac can boot from Thunderbolt.
 

casperes1996

macrumors 601
Jan 26, 2014
4,103
1,998
Horsens, Denmark
Performance

I'm unhappy with Fusion performance.

I've considered selling this (Late 2012) iMac and upgrading to one with straight SSD, but with new iMacs potentially around the corner that seems like a bad move.

I am considering the Lacie 1TB Thunderbolt SSD as a stopgap until we see new iMacs.

Is it possible to boot from software raid on an external disk?

I don't want to split the raid, that would halve the performance and defeat my goals.

I haven't been able to get a straight answer on this anywhere.
What kind of performance are you seeing with your Fusion drive? Have you tried a Black Magick Disk test? (Not really sure how that would even work on a Fusion... Would it use the SSD bit or not?) I was going to get a Fusion with my iMac, but disk speed is quite important to me, and if it's that "bad" perhaps I should reconsider?


Pretty certain the LaCie thing will work btw... Like 90% sure
 

DerekS

macrumors 6502
Original poster
Jun 25, 2007
336
3
What kind of performance are you seeing with your Fusion drive? Have you tried a Black Magick Disk test? (Not really sure how that would even work on a Fusion... Would it use the SSD bit or not?) I was going to get a Fusion with my iMac, but disk speed is quite important to me, and if it's that "bad" perhaps I should reconsider?


Pretty certain the LaCie thing will work btw... Like 90% sure
 

casperes1996

macrumors 601
Jan 26, 2014
4,103
1,998
Horsens, Denmark
Hm...

I'm seeing conflicting info, saying it can only boot if you break the raid. That would halve the performance and defeat the point.
Can't you ask to test it out in a store that sells the drives?

Those speed tests gotta be HDD only... If not, that's incredibly weak speeds
 

DerekS

macrumors 6502
Original poster
Jun 25, 2007
336
3
One of the reviewers on Amazon is running the drive as boot in RAID 0, and on the same model iMac to boot.

I'm giving it a shot!
 

/V\acpower

macrumors 6502a
Jul 31, 2007
549
370
It's possible to split the Fusion Drive (and simply get a 128GB SSD with an HDD.

If what is bothering you with Fusion Drive is what exactly get the "SSD" treatment and what not.

Of course, it depend on how vital is it to you to have SSD speed on ALL of your data.
 

hfg

macrumors 68040
Dec 1, 2006
3,566
277
Cedar Rapids, IA. USA
I have used LaCie "Little Big Disk" Thunderbolt drives which are software RAID-0 and they boot OS X just fine (however, when configured as independent disks it will not boot Windows).
 

casperes1996

macrumors 601
Jan 26, 2014
4,103
1,998
Horsens, Denmark
I'm seeing conflicting info, saying it can only boot if you break the raid. That would halve the performance and defeat the point.
Realized how incorrect I was... Still though, compared to the speeds seen from rMBP and Mac Pro (around 550 mb/s and 1200 mb/s respectively), and considering the fact that it's a PCIe disk, it's still a bit disappointing.

(My disk is ≈65 MB/s, but I remembered it as showing 150, which is why I was so disappointed and confused at first. Thanks for the correction)
 

djzapp

macrumors newbie
Apr 4, 2009
26
0
Laveen, AZ
I currently run a Samsung EVO 250gb SSD through USB3 to boot on my 2013 27inch iMac. While I do see and improvement over a traditional HHD, I am far from true SSD/Flash. Next computer will have it custom ordered to my liking. I am interested to hear if the raid option ends up working for you.
 

SaSaSushi

macrumors 601
Aug 8, 2007
4,084
479
Takamatsu, Japan
I currently run a Samsung EVO 250gb SSD through USB3 to boot on my 2013 27inch iMac. While I do see and improvement over a traditional HHD, I am far from true SSD.
Far in terms of what, benchmarks? I was booting to the Fusion Drive in my Late 2013 iMac and have now switched to a 500GB Samsung EVO in a Thunderbolt enclosure and I see absolutely no difference in daily performance. Now on the other hand, both the external SSD and Fusion Drive are in a different universe when compared to the HDD-only Late 2009 iMac I recently replaced.

Performance-wise, USB3 was even slightly faster for me with the benchmarks than Thunderbolt. Maybe the problem is your enclosure.
 

DerekS

macrumors 6502
Original poster
Jun 25, 2007
336
3
Great Success!

Well, this was a huge success!

I am now booting from external Thunderbolt and getting terrific speeds.



As others have noted, I was unable to directly clone the old disk to the new one.

What I had to do was:

  • Install OSX to the external SSD
  • Restore my Time Machine backup to it
 

jwjsr

macrumors 6502
Mar 15, 2012
333
0
Fairhope, Alabama
I was told by other ,what i consider to be "go to"
MR members, that Black Magic is useless on fusion drives.
If this is true how are you gauging the performance of your fusion drive?
 

DerekS

macrumors 6502
Original poster
Jun 25, 2007
336
3
One last note on this drive - as other reviews have pointed out, the fan is incredibly annoying and loud.

I was able to remove it easily enough.
 

SaSaSushi

macrumors 601
Aug 8, 2007
4,084
479
Takamatsu, Japan
I was able to remove it easily enough.
I recommend you get DriveDX or similar software and keep an eye on your temps. My single 500GB 840 EVO gets pretty darned hot in the fanless aluminum enclosure I'm using. You've got two of them sandwiched together in that compact chassis.

One can only assume Lacie put in the fan for a reason, because it's the single biggest complaint in all the reviews. I'm sure they would have left it out if they thought it viable.

I'm also totally sure they will void any warranty claims you might make if they can prove you removed it.
 

DerekS

macrumors 6502
Original poster
Jun 25, 2007
336
3
I won't be making any warranty claims. I take full responsibility for my hack. :)

Honestly i was about to sell this machine and get a new current-gen iMac with 1TB SSD. This external SSD basically is a stopgap so I can wait for the retinas.

It will last that long for sure.
 

SaSaSushi

macrumors 601
Aug 8, 2007
4,084
479
Takamatsu, Japan
Honestly i was about to sell this machine and get a new current-gen iMac with 1TB SSD. This external SSD basically is a stopgap so I can wait for the retinas.

It will last that long for sure.
Until the Retina iMacs? I wouldn't be so sure about that. The manufacturer's MTBF may have passed by then. :p