Help me configure multiple SSDs

[hfg]

Hi ... I am looking for opinions on how to best configure multiple SSDs in a Mac Pro for speed, reliability, convenience, and usability.

I am currently running a pair of Crucial M4 512GB SSDs in a RAID-0 configuration on a Sonnet Tempo Pro PCIe SATA-III card for OS X, and have a Samsung 256GB 840 Pro on a Velocity x2 PCIe card for Windows 8. I have a 3TB hard disk for archive, music, movies & videos, etc. where speed isn't necessary. This is really fast and works well so far in a new 2012 Mac Pro 12 core.

I grabbed one of the sale priced Samsung 512GB 840 Pro SSDs at Newegg last week, and that has opened up some new possibilities as the performance of the 840 Pro is somewhat better than the M4 drives.

Some alternate possibilities:

840Pro 512GB for OS X on Sonnet PCIe
840Pro 256GB for Windows on Sonnet PCIe
3TB hard disk

840Pro 512GB & 3TB hard disk in Fusion for OS X on Sonnet PCIe
840Pro 256GB for Windows on Sonnet PCIe
(I currently have this set up and running as well )

512GB Samsung SSD partitioned as 2-256GB drives with half Windows, and other half paired with the 256GB Samsung SSD in 512GB RAID-0. Separate 3TB hard disk for slow stuff.
(I am a bit concerned about having Windows and OSX on the same physical drive, when used as part of a RAID array).

And just for fun:
Same as above, but see if a Fusion drive can be created with a RAID-0 array and a hard disk. Can you do this??

I am not concerned about "increased failure rates from multiple drives" as I have a good backup system in place and drive failures are hopefully infrequent.


What would you suggest ... and why?

Thanks,
-howard

 

[KaraH]

fusion? eek! run away! run away!

 

[hfg]

fusion? eek! run away! run away!

Oh, Fusion's not that bad ...

I have been playing around with DIY "Fusion" setups since they were first announced and haven't found them to be a problem.

I do prefer all SSD when possible, but the Fusion may have some benefits here with keeping active files on the SSD while the remaining majority of the folder resides on the hard disk ... makes maximum use of the available SSD space.

Note that my DIY Fusion here is a 512GB SSD paired with a 3TB hard disk, not the Apple endorsed smaller 128GB SSD. This keeps most all of my active files on the SSD all the time, but allows for a normal OS X file structure in my user folder.


-howard

 

[Tesselator]

Hi ... I am looking for opinions on how to best configure multiple SSDs in a Mac Pro

And just for fun:
...see if a Fusion drive can be created with a RAID-0 array and a hard disk. Can you do this??

I dunno yet. But my bet is that yes, it can be done.

What would you suggest ... and why?

Thanks,
-howard

It looks to me like you have it sussed already. You might even be the teacher who instructs us on RAIDing Fusion drives.

After profiling the file sizes and access frequencies myself by hand however, I think I would follow more closely Apple's own suggested balance for SSD to HDD size ratios. I actually think 32GB or 64GB SSD on a 3TB HDD is the sweet spot for fusion setups containing Apps and the OS.

Let us know what you find out about RAIDing Fusion drives.

 

[hfg]

Just to answer my own questions if anyone is reading this thread (for closure)...

Well ... it does appear that you can create a DIY Fusion drive with a RAID-0 disk(s) array.

I used a 512GB and a 256GB Samsung 840 Pro SSDs. I split the larger 512GB SSD in half, and used one half for a bootable Windows installation, and the other half along with the smaller SSD to create a 512GB RAID-0 array. I then used the often published technique to use Terminal commands to create a DIY Fusion drive joining the 512GB RAID-0 SSD with a 3TB hard disk.

It all went smoothly, except when installing OS X 10.8.3 downloaded from the App Store, the installer complained that it couldn't create a "restore partition" and it refused to continue to complete the installation. I am used to seeing a warning when installing OS X to a RAID-0 array that some features will not be available such as restore and encryption, but you can dismiss the dialog box and complete the installation. Apparently, seeing a RAID-0 in a Fusion drive is not cleanly handled in the installer.

However, the Fusion logical drive was already created, so I simply used CCC (Carbon Copy Cloner) to clone my existing installation, rather than doing a clean install with data migration as I had intended.

So far, everything seems to be working as expected.

-howard


Here are some DiskTest results on the Sonnet Tempo Pro PCIe card:

Left: Fusion with RAID-0 Samsung 840 Pros .................... Right: dual Crucial M4 RAID-0
.