First Feedback on Univ. (3rd party SSD) Trim Enabler in Lion GM
(Apple shipped SSDs should have trim enabled w/o any patches - many missed past posts on this and keep writing about native Apple SSD trim support.)
First report on Lion/GM using TRIM Support Enabler 1.2 (for NON-APPLE SSDs):
"Feedback on SSD Trim enabler and 10.7 GM (11A511)
I wanted to drop a note and let you know that I have tried the TRIM enabler (v1.2) with GM 10.7 (11A511) and it is successful in enabling TRIM for non Apple branded SSDs.
(For the record I asked for info on SSD used.-Mike)
I used the OWC Mercury Extreme Pro SSD 240GB (from early 2011) on both systems. I've had no issues with the sleep or freezes.
(IIRC OWC does not recommend trim enabling, as their stance is that it's not needed for those (Sandforce-based) SSDs to maintain performance.
Update: - a week later (July 15th) OWC posted a blog entry saying they don't recommend trim for their SSDs, and that enabling Trim may cause issues with them.)
(FYI: I wrote to confirm this but assume Lion still did NOT have SSD Trim enabled by default for his OWC/sandforce SSD - otherwise why would he have applied the patch.-Mike)
You are correct, for this (non-apple) SSD it was NOT enabled until patch was applied..
I have used it for various days and everything works as expected.
My friend has tried an old version of the Vertex and he had issues both in 10.6.8 and 10.7 Developer Previews, to the point where he was returning it as the problems were there with or without TRIM enabled.
Best regards,
Luis"
I don't have an SSD installed in anything currently but welcome other reports on this from other OS X users.
The June 30th news has a couple previous reports on the Univ. Trim patch w/OS X 10.6.8. (Intel SSD owner reported OK, but a Vertex3 SSD owner said he had problems (freezes, etc). Asked him to confirm if it was OK long-term otherwise since some have had SATA3 drive issues with some (not all) new MBP samples. (One owner swears it's due to luck of the draw with OEM cable quality at SATA3 rates - based on a cable swap from an OK MBP into his previous one that had major SATA3 drive problems.)
A reader sent a note on some reports of Trim + GC issues from OS X users. (SSD Garbage Collection (GC) support has always been a big plus for OS X users since we did not have TRIM support in the past.)
"You might want to note that enabling trim is not recommended for drives that have built in aggressive garbage collection built in. (Any mfrs posted a definition of "Aggressive" vs std (idle time) GC?-Mike) Pretty sure there's good reason apple doesn't just turn it on for all drives by default.
(IMHO the main reason Apple doesn't enable TRIM for other than what they source/ship is to avoid -any- possible support issues (calls, costs, etc) with 3rd party SSDs they have not tested. I totally understand the reasoning, which is nothing new. (I suspect many mfrs would call it business common sense.)
Remember how many -years- it took to even get basic universal CD burner support? (for other than drive models they shipped in macs.) We used to post burn support (edited) files, then patchburn utility was released to automate that for 10.2/10.3. Finally in OS X 10.4 (and later) those patches were not needed.-Mike)
if (you) read the comments on the trim enabler home page, (www.groths.org/?p=308) you will see a number of posts who saw massively degraded performance with trim enabled. The author of the enabler himself said that you should google your model ssd drive to see if it has native garbage collection and only enable trim if it doesn't.
Some still don't heed that advice and only see a feature they think they should have that they don't and enable it on poor understanding.
-Adam"
I know what you're saying - human nature to always want more. If you're pleased with your SSD performance as is - there's no reason to mess with it. And don't do 'unsupported' mods unless you're willing to accept the risk of problems. (But I'm sure you already know that.) And of course it goes without saying you should not enable Trim if your SSD doesn't (reliably) support it. (Like GC, Trim must be supported in firmware for it to work, not just in the OS. And totally bug-free firmware/software/drivers isn't a given. Even the 3rd update (in appx 1yr) for my SSD still noted major bugs were being fixed.) OS/driver bugs are also common on any platform.
But at least this patch gives OS X users of non-apple shipped SSDs an option to try it if they want. Some had positive experiences, some not. (The patch can be undone, but always have a backup of your drive in case things go really south - that can happen anytime, anyway.)
I could be wrong but until I see some mfr's confirmation on a common problem with SSDs that have Trim + GC support, my gut reaction to this is that it's more likely an issue with Trim alone than in combination with GC. (Could be related to OS X's current implimentation and/or with a specific SSD series/controller/firmware version, bugs etc - or some other unknown factor.) And to state the obvious, as shown in the original post here in March on manually 'Enabling' Universal (not just Apple shipped SSDs) TRIM support (which also had verification that it worked on the hardware he used) - all that is done is to neuter the apple SSD name ID check. There's no guarantee that TRIM will be trouble-free (in ANY OS) with every SSD/user's configuration. I don't blame the author for posting a disclaimer/warning as he can't test every ssd/config. (Neither can Apple, as even their most basic updates (and owners of unmodified macs) often have lots of problem reports - not that most are universal.)
If anyone has a link to a mfr's comments on negative performance issues with Trim enabled on a SSD that supports GC, send the link and I'll post it. (Apologies for not digging for it myself - and asked Adam to send specific links he referred to. Added the Trim patcher home page link to the post.)
Although not always 100% accurate, here's wiki pages on TRIM and SSD Garbage Collection. (In the past I've posted links to SSD tech articles from anandtech and other sites on these subjects but don't have those links handy. Maybe there was something on this issue there in the past and I missed/forgot it.)
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