Apple Adds SSD Trim Support to OS X 10.6.8 Update

It’s been known for a little while that OS X 10.7, ‘Lion’, would offer support for the ATA ‘TRIM’ command, but for those who weren’t planning to make the leap to Apple’s latest OS, that became a tough feature to ignore. Well, don’t fret, because it turns out that the 10.6.8 update Apple rolled out last week quietly added the feature in.

Many PC users who’ve adopted an SSD no doubt know what TRIM is, but on the Mac side, it’s not been a topic covered too heavily. Essentially, TRIM is a low-level command that gets passed to an SSD whenever a file is deleted which wipes the blocks totally clean, rather than mark them as ready for overwriting. In layman’s terms, this means that your SSD will continually be kept in good performance shape, rather than slow down over time – a problem non-TRIM SSDs are stuck with.

In typical Apple fashion, there’s a major caveat to be aware of with this feature. It does not support SSDs that weren’t installed by Apple itself. If you purchased a MacBook Pro this year, chances are it does have a compatible SSD, but if you have an older model or any other Mac and installed your own SSD, you’re out of luck.

Because TRIM is a universal command and not one specific to a certain vendor, this is a limitation that should be able to be worked around. Hopefully a common and simple-to-enable fix will come out sooner or later, either from Apple or someone else. It’s a bit alienating to offer the feature and deliberately block access to it to those who opted for their own SSD (which in all likelihood is better what whichever SSDs Apple uses).