New in OS X: Get MacRumors Push Notifications on your Mac

Resubscribe Now Close

Mac OS X 10.6.8 Brings TRIM Support for Apple SSDs, Graphics Improvements [Updated]

One item of interest regarding last week's Mac OS X 10.6.8 update reveals that Apple has enabled TRIM support retroactively for solid state hard drives shipped in Apple-produced configurations. TRIM is a feature that allows solid state drives (SSDs) to automatically handle garbage collection, cleaning up unused blocks of data and preparing them for rewriting, thereby preventing slowdowns that would otherwise occur over time as garbage data accumulates.


Support for TRIM has been included in OS X Lion since its early developer builds, but Apple has apparently decided to push the feature out to Snow Leopard users as well. The new native TRIM support does appear to limited to stock Apple drives, as users who have installed third-party SSDs into their machines have reported that TRIM is not enabled by the update.

Mac OS X 10.6.8 also appears to have brought graphics improvements that have been most apparent to gamers. According to one set of benchmarks, Mac OS X 10.6.8 outperforms Mac OS X 10.6.7 in many measure of graphics performance, sometimes by a significant margin.


User reports in the MacRumors forums and the Steam forums similarly point to significant improvements in graphics performance under real-world conditions. A number of users has actually reported significant declines in graphics performance with Mac OS X 10.6.7, so improvements with the new Mac OS X 10.6.8 are certainly to be welcome.

Update: To clarify Apple's TRIM support, the new MacBook Pros released in February shipped with a special build of Mac OS X 10.6.6 that included TRIM support for Apple SSDs. But that TRIM support had not been extended to all SSD-configurable Macs until the release of Mac OS X 10.6.8 last week.

Update 2: A number of users of pre-"Late 2010" MacBook Air models have reported that Mac OS X 10.6.8 does not enable TRIM on their machines.

Top Rated Comments

(View all)

46 months ago
Only for official Apple drives?

Ouch! :eek:
Rating: 14 Votes
46 months ago

Apple is not in the business of writing firmware for every storage vendor's devices. Apple has created support for TRIM in the operating system. Get on your device's manufacturer's case for adding support for it in OS X.


Windows 7 supports TRIM on a wide range of SSDs, and there are third party hacks that enable TRIM on any SSD where the firmware supports it (which is almost every drive shipped now). It wouldn't be difficult for Apple to do the same.
Rating: 9 Votes
46 months ago

Apple is not in the business of writing firmware for every storage vendor's devices. Apple has created support for TRIM in the operating system. Get on your device's manufacturer's case for adding support for it in OS X.


TRIM is a standard ATA feature, similar to SATA 6G. There's no need for Apple to write firmware or drivers for anyone in order to support it. Either a SSD has the capability (which will be announced to the OS if it asks nicely), or it doesn't. In the latter case, it won't work on Windows or with TRIM Enabler either. Apple has just decided not to enable it on other drives for political reasons. There's no technical reason. Windows supports TRIM generally, so could OS X.
Rating: 8 Votes
46 months ago
Don't care for TRIM support unless its for Intel, OCZ and other superior third party SSD drives. Apple's toshiba rebranded drives are a joke.

What is their excuse for not supporting other drives?
Rating: 8 Votes
46 months ago

What if they are? If you want a file, don't delete it.
No offense, but why would you want to recover a deleted file? I mean you already have the option to recover it from the trash... If you delete it from the trash then you probably don't need it at all (or you should have thought better)


No offense, but you're putting a lot of words into his mouth. He just asked if it made deleted files unrecoverable more quickly. For all we know, he might consider that a GOOD thing. I know I do. :)
Rating: 8 Votes
46 months ago
Did anyone try the trim enabler application on 10.6.8 with third party SSD?

edit: nevermind, a new version was released by the author (http://www.groths.org/)
edit2: just applied the trim enabler and it is working now on 10.6.8
Rating: 6 Votes
46 months ago

...a SSD with a SandFore (trim handled by controller).


Sandforce cannot do TRIM in the controller. It can run proactive garbage collection in the background to help ensure an adequate pool of erased pages. This keeps performance high as long as the SSD has a big pool of "invisible" pages - but it also causes unnecessary wear on the drive as the garbage collection will copy unused data while garbage collecting.


(it sure sounds like it because TRIM support is simply about issuing a command to the controller, right


Apple is not in the business of writing firmware for every storage vendor's devices. Apple has created support for TRIM in the operating system. Get on your device's manufacturer's case for adding support for it in OS X.


TRIM is a standard (albeit optional) SATA command. It is a simple command where the OS tells the drive that "sectors XXX through YYY are free".

It has nothing to do with "Apple writing firmware". If the drive identifies itself as "TRIM support=YES", then the OS simply adds the "send TRIM command" to the file system code that puts blocks on the file system free list.

That's why Windows supports TRIM on any device that claims it supports TRIM.


Good drives- like Sandforce or Intel based SSDs-- do not need TRIM. TRIM is only useful for dumb flash drives, and you shouldn't use them anyway, because, even with TRIM their useful life is likely to be only a couple years.


"Good drives" are "better drives" if you can send them TRIM commands. While the performance of Sandforce drives holds up better than earlier drives, TRIM will help them last longer.

Can you name any drives with 2 year MTBF?
Rating: 5 Votes
46 months ago

Windows has to support Trim generally, since otherwise it would be virtually useless in light of Windows' licensing to multiple vendors. Since Apple isn't licensing OS X to any other vendors, they don't have to support Trim generally. It's not "political," it's practical.


Huh?

TRIM is a standard but optional ATA feature.

When you buy an SSD, it will report to the OS whether it supports TRIM as part of the device identification protocol.

Apple are being d#ckheads in ignoring the device's support for TRIM if it isn't one of the Apple supplied SSDs.

Windows is simply accepting the device's claim that it supports TRIM, and if so sending the TRIM commands to the device. Licensing has nothing to do with it - Windows is simply accepting the device's claim that it supports TRIM.
Rating: 5 Votes
46 months ago
The graphics improvements are very welcome.
Rating: 4 Votes
46 months ago

Does this mean that deleted files will be rendered unrecoverable fairly quickly?


Yes, before you've even moved you hand away from the [OK] button. ;)

Actually, though, it depends. If "delete" moves the files to a "trash" directory or "recycle bin" - there's no difference from a system without TRIM.

If "delete", however, actually "permanently deletes" the file - with TRIM it will be extremely unlikely that it is recoverable by any "find deleted files" utility.

Those utilities usually work on the assumption that the file system meta-data for the file is marked "deleted", but in fact the rest of the meta-data and the actual file data is still intact. These "deleted" entries will in fact be correct until the meta-data record or the actual file data is overwritten with a new file. If you run the "find deleted files" utility, it looks for meta-data records marked "deleted" - and will try to recover the file.

With TRIM, however, a command is sent to the solid state drive to notify it that the file data is free. The drive will add those sectors to a background task that erases free space and puts in on the available list. (Unlike a spinning hard drive, SSD sectors cannot be simply overwritten with new data - the sector (usually a "page" containing quite a few sectors) must be "erased", and then it can be written.)

The key to maintaining SSD performance is to ensure that the drive has a big pool of already erased pages. That lets a write completely quickly. If there are no free pages, then the drive has to move a bunch of sectors out of a page into partially used pages, and then erase the page, and then write the incoming sectors into newly erased page. This can make writes much slower.
Rating: 4 Votes

[ Read All Comments ]