Ever since the release of OS X 10.6.8, Apple has been selectively enabling the TRIM command for SSD’s in OS X. This support continues on on Mac OS X Lion, as well as Mountain Lion, but as many have noted, it only seems to work for Apple SSDs. Here’s how to enable TRIM across the board:

The TRIM command is an important disk command for SSDs that keeps your flash memory appropriately cycled so that you can achieve faster read and write speeds, as well as a longer lifespan for your SSD. As such, TRIM support is not the trivial matter that some make it out to be (although certain manufacturers, such as Other World Computing, include firmware that eliminates the need for OS-level TRIM support).
In you have an SSD that supports TRIM, and you’re running OS X 10.6.8 or Lion, follow the below instructions to enable TRIM. Note: This involves the use of terminal commands, so proceed at your own risk.
TRIM can be enabled by using the Terminal commands contained within this document.
Simply right click and download this DOC file to find out how to enable TRIM support for all SSDs in OS X Lion.
*Update: I’ve received a few emails saying that some of you are having issues with the DOC file, so I’ve uploaded this RTF file as well, which should fix any issues you may be having.
A free app called Trim Enabler is also available (link) – but while Trim Enabler makes things simpler, it isn’t as reliable as using the terminal command.
If you’re looking for an SSD to use in your Macbook, I recommend checking out the OCZ Vertex 4 or the Sandisk Extreme.
For more helpful tips, check out our full collection of tutorials by visiting our How-To category!
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