Adding an SSD to a hackintosh HD installation
There is much interest in Apple’s new Fusion Drive for Macs, where an SSD and conventional Hard Drive are paired into one drive. Files are automatically moved between the SSD and HD depending on usage, so the most frequently accessed files reside on the faster SSD and the HD provides greater capacity for infrequently used files. The feature sounds like a step forward for users with more files than a reasonably priced SSD can store, but there are still many answers and reliability tests needed before it’s something to recommend for use on a hackintosh.
After recently buying a 128Gb OCZ Vertex Plus SSD from Aria, for the bargain price of £40, I have been looking at ways to use this with my 2Gb hard drive. I recently added a Seagate 2Gb 7200.14 drive, using my previous 2Gb drive as a backup. The new Seagate gave a big boost to read/write performance, going from around 50Mb/s read/write on the old HD to 140Mb/s read/write on the Seagate 7200.14. This testing was done using the free Blackmagic Disk Speed Test app for the Mac appstore, so while in no way comprehensive does show a big speed increase for sequential access.
The OCZ Vertex Plus SSD is an older generation device that gives around 160Mb/s write and 200Mb/s read speeds. This is way below the 500MB/s+ speeds that newer SSD’s can offer, but this was intended as a cheap test before committing to a more expensive SSD. The next decision is how to use the two drives, with three main options available:
- Install everything on the SSD, then tell individual applications to move their data files to the Hard drive. An example would be moving the iTunes library to the hard drive and pointing iTunes at it.
- Install everything on the SSD, then move either a single user account or the /Users folder to the hard drive. This method uses symbolic links and/or settings for the user account.
- Install everything on the SSD, then move selected large folders from the user account to the hard drive. This could include the music, movies and photo’s folders. Use symbolic links to make the OS think these are still on the SSD.
The first option involves lots of configuration in different applications, and the third requires making a symbolic link for each folder that is moved. My choice was the second option, which while not quite as fast as the third option (user Library folder with preference files is on the slower hard drive) is a lot simpler to manage.
The hackintosh already had a 2Tb volume (named HD2TB) containing a full installation with Applications, Library, System and Users folders. I wanted to clone everything except my user account (named macpro) to the SSD. Using the worth-every-penny-even-though-it’s-no-longer-free Carbon Copy Cloner I select everything except /Users/macpro and cloned this to the 128Gb SSD. My 2Tb drive was around half full, with 965Gb in my macpro account and 55Gb in Applications+Library+System. This put 55Gb on the SSD, which included a “Temp” user account to log into when booting from the SSD. Multibeast from TonyMacX86 was then used to install the Chimera bootloader on the SSD.
Next step was to boot from the SSD, and log into the “Temp” account. I opened System Preferences then Users & Groups, and found that although I had not cloned the contents of my user account (at /users/macpro), it was listed in the Other Users list. Holding the Control key while clicking the macpro account showed the advanced options menu. The Home Directory option was changed from /Users/macpro to /Volumes/HD2TB/Users/macpro.
Logging out of the Temp account and into the macpro account displayed my desktop as I expected. All the files were present on the desktop and some apps would work fine. The problem came when launching something like Adobe Lightroom that looked for its library at /Users/macpro/Pictures/Lightroom and could not find it as it had moved to /Volumes/HD2TB/Users/macpro/Pictures/Lightroom. The solution is either manually set the location for all Apps that require it, or use one symbolic link to the user accounts.
Using Terminal I navigated to the root of the SSD, and typed:
sudo rm -rf Users
This deleted the Users folder from the SSD, which was fine as the user accounts I wanted were on the hard drive. Next I created a symbolic link to the Users folder on the hard drive:
ln -s /Volumes/HD2TB/Users
Now whenever anything (app or OS) looks for /Users/macpro it is redirected to /Volumes/HD2TB/Users/macpro. I will have to make two backups now, one of the SSD with the operating system, and one of the HD with user accounts. The backup HD can be partitioned into a 128Gb partition to backup the SSD and the rest to backup HD2TB.
This also gives me the option of cloning the 128Gb OCZ SSD to a faster SSD in future without touching the user accounts on the HD. The Samsung 830 series SSD’s are recommended for Mac’s, so with the 128Gb version available for £80 a clear upgrade path is available if required. Application launching with the OCZ SSD has dropped from several bounces of the app icon in the dock to one bounce, so for now the speed increase for booting and application launching is just fine.