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Forked from clarencesong/
Created November 21, 2012 11:10
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Enable TRIM in OS X 10.8.2 for IOAHCIBlockStorage version 2.3.1
Enable TRIM on non-Apple SSDs in OS X 10.8.2 Mountain Lion.
WARNING: This is ONLY tested on 10.8.2 (IOAHCIBlockStorage version 2.3.1), and NOT earlier or later versions.
Check /System/Library/Extensions/IOAHCIFamily.kext/Contents/PlugIns/IOAHCIBlockStorage.kext/Contents/version.plist
Technical note: The driver changed in 10.8.2 and similar perl commands that worked in earlier OS X versions did not work for me once I updated to 10.8.2.
Run the following commands in Terminal…
1. Backup the original driver
sudo cp /System/Library/Extensions/IOAHCIFamily.kext/Contents/PlugIns/IOAHCIBlockStorage.kext/Contents/MacOS/IOAHCIBlockStorage /System/Library/Extensions/IOAHCIFamily.kext/Contents/PlugIns/IOAHCIBlockStorage.kext/Contents/MacOS/IOAHCIBlockStorage-backup
2. Modify the driver
sudo perl -pi -e 's|(\x52\x6F\x74\x61\x74\x69\x6F\x6E\x61\x6C\x00{1,20})[^\x00]{9}(\x00{1,20}\x54)|$1\x00\x00\x00\x00\x00\x00\x00\x00\x00$2|sg' /System/Library/Extensions/IOAHCIFamily.kext/Contents/PlugIns/IOAHCIBlockStorage.kext/Contents/MacOS/IOAHCIBlockStorage
3. 2 commands to clear the system caches to enable OS X to pick up the modified driver
sudo kextcache -system-prelinked-kernel
sudo kextcache -system-caches
sudo touch /System/Library/Extensions/
4. Restart the Mac
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gbdoin commented Feb 26, 2013

Original gist didn't work, with this fork, everything works! THX!

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goodloop commented Mar 5, 2013

Great, successed

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ashoaib commented Mar 14, 2013

Thanks for this! This works on 10.8.3 (12D78), IOAHCIBlockStorage version 2.3.1.

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Thank you. But, it doesn't work for me (IOAHCIBlockStorage ver 2.3.1) and 12D78

Did everything exactly as in the writeup. Any ideas why?

UPDATE: Works with the patcher that I found -->

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I'm in the same situation as brilligence.

My SSD is an INTEL SSDSC2CW240A3, and it's plugged into the second SATA port (I removed the optic drive and put an SSD instead). I have an APPLE SSD on the first SATA port.

UPDATE: oops, forgot to update caches :-/. Sorry for the noise.

I ended up backing out of enabling TRIM on 10.8.3 after seeing the number of people who rendered their system unbootable by trying.

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Thank you leolimajr! I've been looking all over for this.

I'm running OS X 10.8.3 on INTEL SSDSC2CW240A3. The above code worked for me. I modified my existing bash script to include the "x54" hex code. Previous script used on 10.8.2 (note "x51" diff):

sudo perl -pi -e 's|(\x52\x6F\x74\x61\x74\x69\x6F\x6E\x61\x6C\x00{1,20})[^\x00]{9}(\x00{1,20}\x51)|$1\x00\x00\x00\x00\x00\x00\x00\x00\x00$2|sg' /System/Library/Extensions/IOAHCIFamily.kext/Contents/PlugIns/IOAHCIBlockStorage.kext/Contents/MacOS/IOAHCIBlockStorage

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x128 commented Mar 28, 2013

Thanks! TRIM enabled on 10.8.3 (12D78), SSD OSZ Vertex 4.

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Thanks for the tip guest4562345, working for me as well now.

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tzucc commented Apr 10, 2013

worked successfully on reboot... Trim Enabler app could not do anything, Leo's script fine as is ... OS X 10.8.3 (12D78) ... Macbook Pro mid June 2012, Samsung Pro 500GB.

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Thanks leolimajr! Patch working for me too. 10.8.3 ( 12D78 ) MacMini Mid 2010 with Crucial M4 (CT128M4SSD1).

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Thanks a lot leolimajr! It's working on 10.8.3, Early 2008 15" MBP & Intel 335 240GB.

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confirmed working on 10.8.3 (12D78) with Crucial M4-CT256M4SSD2 (installed in CD-ROM port)


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