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View Full Version : TRIM support in Lion?




Legion93
Apr 8, 2011, 11:04 AM
I've heard from AppleInsider that TRIM is long due to the macs and that Apple will enable TRIM support in Lion update...

After I've installed an Intel x25-m G2 SSD onto my 2010 MBP 13", the benchmarks were low compared to that on Windows platform. I also noticed the Apple's own stock SSD (mostly Toshiba or Samsung) have aggressive GC, but their read/write speeds are off compared to many decent SSD's on the market, like sandforce powered OCZ Vertex 3, or intel G3.

Funny thing is that Apple's own solid state drives has their own GC, and enables TRIM on-the-fly, as reported by Anandtech, but I wasn't very sure.

Has anyone have any ideas if and when TRIM will be implemented on macs, since it is really needed for people with SSD's in their macs?



alvindarkness
Apr 8, 2011, 11:20 AM
I've heard from AppleInsider that TRIM is long due to the macs and that Apple will enable TRIM support in Lion update...

After I've installed an Intel x25-m G2 SSD onto my 2010 MBP 13", the benchmarks were low compared to that on Windows platform. I also noticed the Apple's own stock SSD (mostly Toshiba or Samsung) have aggressive GC, but their read/write speeds are off compared to many decent SSD's on the market, like sandforce powered OCZ Vertex 3, or intel G3.

Funny thing is that Apple's own solid state drives has their own GC, and enables TRIM on-the-fly, as reported by Anandtech, but I wasn't very sure.

Has anyone have any ideas if and when TRIM will be implemented on macs, since it is really needed for people with SSD's in their macs?

TRIM is already implemented on Lion. You can even enable it on 10.6.7 if you use the IOAHCIFamily.kext from a 2011 MBP.

The trick is that both Lion and 10.6.7 (using the MBP 2011 kext above) look for an SSD with the model name "APPLE SSD". What you need to do is hex edit IOAHCIBlockStorage.kext/Contents/MacOS/IOAHCIBlockStorage and replace the two instances of "APPLE SSD" with the first 9 character of your SSD drive as it appears in system profiler. (In my case "OCZ-VERTE").

Theres a lot more information here -> http://forum.hardmac.com/index.php?showtopic=10020

And heres confirmation that it does indeed work (this is a snow leopard pic, Ive also done this in Lion).

280293

The real question is, wether this is a stop-gap measure, or if Apple intend to continue this trend into the future and only support trim on native apple ssd's. Would be nice to not have to load a hex editor after every delta/combo update.

MikhailT
Apr 8, 2011, 11:20 AM
The official TRIM support is already in Snow Leopard builds for the new Macbook Pros with SSDs and it's in Lion as well. The official support is only for the Apple's SSDs, no TRIM support for third party SSDs. There is a way to enable it for any SSD that supports TRIM, but it is a hack. Here's the thread: http://forums.macrumors.com/showthread.php?t=1125400

Apple are usually conservative about their SSDs, they don't go for the top of the line SSDs. So, it is normal to see conservative speed from Apple's SSDs.

Legion93
Apr 8, 2011, 11:45 AM
The official TRIM support is already in Snow Leopard builds for the new Macbook Pros with SSDs and it's in Lion as well. The official support is only for the Apple's SSDs, no TRIM support for third party SSDs. There is a way to enable it for any SSD that supports TRIM, but it is a hack. Here's the thread: http://forums.macrumors.com/showthread.php?t=1125400

Apple are usually conservative about their SSDs, they don't go for the top of the line SSDs. So, it is normal to see conservative speed from Apple's SSDs.

TRIM enabler is a hack, and some people have reported that their read/write speeds have dropped significantly after installing it on their macs. I'm worried that it even does the job, but I am guessing it just changes the kernel so that instead of saying 'No' it says 'Yes' under TRIM support in SERIAL-ATA.

alvindarkness
Apr 8, 2011, 12:04 PM
TRIM enabler is a hack, and some people have reported that their read/write speeds have dropped significantly after installing it on their macs. I'm worried that it even does the job, but I am guessing it just changes the kernel so that instead of saying 'No' it says 'Yes' under TRIM support in SERIAL-ATA.

It's not just changing the No to a Yes. You can confirm TRIM is working by using hfsdebug and dd, with and without the patch. The beachballs people get could be due to an over aggressive use of TRIM by the current kext's, guess we'll find out sooner or later.

maflynn
Apr 8, 2011, 12:33 PM
Given that apple added TRIM support in SL (and there's an easy hack to enable it for non-apple SSDs), I'd say its a slam dunk to think it will be in Lion