Mac comes with a Solid State Drive provided by Apple and enables trim for it only. If your Mac is upgraded with aftermarket SSD, Mac will not be able to use trim with it which will reduce the performance of the drive.
Mac OS X 10.10.4 comes with the feature, enabling TRIM with just a single on any SSD which is in your Mac. No longer you are required to turn off the security feature and modify your system to perform the action.
Why TRIM is Important and Why Macs Don’t Always Enable It by Default?
When operating system uses solid state drive with the TRIM, a signal is sent to SSD every time when a file is removed. The SSD knows that file has been removed and it erases the file’s data from its flash storage. With the flash memory it is easy to write on the empty memory. If you want to write on the full memory, the memory first must be erased and then use it for writing. Unless TRIM is enabled this thing often slow down the SSD.
Window 7 and the newer version of window has the built in support for the Trim, which is enabled for all SSDs. In Mac as the Trim works at the low level and this lockout them. Starting from the OS X 10.10.4, apple is now providing official but unsupported way of enabling TRIM for any SSD.
Is it safe to enable TRIM on your SSD?
Well, the answer to this depends on the SSD you are using in you Mac. Apple does not want to be responsible for any problem which is the reason why OS X hides this functionality behind the command and frightening warning message. TRIM is implemented by many of the SSD but in the slightly different ways and many of the SSD manufacturers truly test the compatibility on the windows. A search company Algolia pointed out the data corruption bugs, as they use SSDs with TRIM on the Linux and some same cases may occur if you enable TRIM for such drives using Mac. There are also some reports of some crucial drives not functioning properly with TRIM on Linux.
Activate trim with trimforce:
In the minor update to OSX 10.10, Apple silently added the command of trimforce. This is also available in OS X 10.11 El Capitan.
This command helps to activate TRIM for every SSD contained in your Mac. This disables the check, allowing TRIM to work with Apple provided OEM SSDs. When you run it, TRIM will be enabled for all your Solid State Drives. There is no any other ways that enable TRIM for one SSD and leave that disabled for another.
There is warning that you are doing this at your own risk. This is a better thing that you always have a backup of your important files.
To run trim force, open the terminal window and type the command.
sudo trimforce enable
when screen will prompt type the account’s password. To agree with scary message press ‘y’. Your Mac will be rebooted after pressing Y again and the TRIM will be enabled for all SSDs.