Upgrade to Yosemite with two hard drives in iMac I'm running 10.9.5 on an iMac, where I have two hard drives (SSD + HDD) and Superdrive installed. The way the disks are mounted is not conventional:

/dev/disk0s2 on / (hfs, local, journaled)
devfs on /dev (devfs, local, nobrowse)
/dev/disk1s2 on /Users (hfs, local, journaled)
map -hosts on /net (autofs, nosuid, automounted, nobrowse)
map auto_home on /home (autofs, automounted, nobrowse)


disk0s2 is internal SSD drive and disk1s2 is internal 1TB HDD drive.

I've read that upgrading to Yosemite will convert my drives to fusion drive1, though I have not found detailed information what would happen in my situation. I have a couple of questions:


did anybody try upgrading Mavericks to Yosemite with similar drive configuration? What were the results?
will Yosemite convert my two drives to Fusion drive? (I read that in order to convert it, it needs to erase contents, so I'm assuming that upgrade procedure won't create fusion drive)
if the fusion drive will be created automatically, I guess I can't control which data is on SSD and which data is on HDD anymore, right? I use virtual machines heavily (vmware) and I don't want them all on ssd...


Since this machine is my primary workhorse, I'm reluctant to just try and see if it works. I've upgraded my Macbook air (single ssd drive) without issues, fwiw.
The answer is: OS X did not upgrade my disks to Fusion Drive (or CoreStorage).

[miha:~]diskutil cs list
No CoreStorage logical volume groups found


Probably because of the unconvetional layout. Or perhaps some other unknown reason.