The time has finally arrived. TRIM support for all capable SSD drives in Mac OS X. w00t! This little freeware app pictured above is the hallmark of all my hopes and longings for SSD use in Mac OS X. But why is this app worth such excitement? Well, it might first help to get a quick primer on the merits of TRIM, and where else to find such a definitive guide than Anandtech.com. Give this page a read, and you’ll almost be an expert on TRIM support.
So now that you know what TRIM is, and how it improves SSD write performance, we can talk about how it works in Mac OS X. Wait, you did read that link, right? Go on, make sure you at least skim through it. We’ll wait . . . . . . . . . Ok, finished? Good, let’s continue:
While Windows 7 has had TRIM support as a basic component of the operating system from its initial release, Mac OS X has yet to officially embrace TRIM support. That’s despite an almost 2-year lead that Microsoft has had on a crucial performance boost to SSD use over OS X. And that’s also in spite of the face that most Apple laptops and desktops offer SSD CTO (“configure to order”, not some fancy technical jargon) options.
The question everyone has been asking is why is it taking so long for Apple to adopt TRIM support? It’s not all that hard, from a technical perspective. And several times, when a point release (10.6.#) would be announced, rumors abounded that Apple would finally be giving their SSDs a real-world performance boost. Alas, it was not to be (for whatever reason).
The big break came with the release of the developer preview of Mac OS X Lion (10.7), which is rumored to be officially released to the public at WWDC in June. When people tested out the developer preview, they noticed a new bit of information displayed in System Profiler: “TRIM Support.” That announcement itself was exciting, because it meant that at least in the developer preview, Apple was readying support for TRIM. As other developer versions have unfortunately sported features that never made the final release, it was a bit worrisome that Apple might pull the plug at the last second (the fate that ZFS was dealt).
But while even the developer preview was nice to have, as different developers tried the new OS X build on their own systems (sporting a variety of different SSD options), it quickly became apparent that the actual list of supported SSDs was very limited. Although no official list has appeared, many of the common SSDs from manufacturers like Corsair and OCZ weren’t on Apple’s guest list. The only drives we’ve seen support for are the SSD options that ship as CTO from Apple. It makes sense from Apple’s traditional strategy for hardware, but it was nonetheless frustrating for those without a CTO SSD who wanted to boost the performance of their Mac.
That’s where the loophole appeared: TRIM support was not limited to just the developer build of Lion, but was able to be ported back to Snow Leopard (10.6.7 required). Intrepid hackers managed to figure out that the TRIM support built in to the developer preview of Lion was in fact generic support for any model! That Apple artificially limited support to their own SSDs was not surprising, but now at least the barriers have been removed! (Who knows, maybe Apple will enable support for all TRIM-capable SSDs when Lion is officially released, but don’t hold your breath).
So if you’re running a Mac with an SSD, make sure to get the latest update to 10.6.7 for Snow Leopard and download the nifty little tool from the publisher’s website. If you’ve been holding off from installing an SSD in your Mac until this support came through, now’s the time to jump on the SuperSonicDrive bandwagon. (Kudos if you knew enough to hold off for TRIM support; I did not have that kind of discipline myself). And if you’re doing the Hackintosh thing like me, your awesome OS X machine just got awesome-r.