We have known and we have recommended for a while now that having an SSD drive as your boot or system drives was a worthwhile upgrade. However in the Mac world the issue of the TRIM command has been an area of confusion. However one company have done away with that confusion. Angelbird are the only SSD manufacturer that produce SSD drives that support the native Apple TRIM command. In this 3 part review we are going to take a look at their SSD wrk for Mac Pro, an example of their portable drives, in this case a lovely blue SSD2go pocket drives, but first a look at what makes Angelbird drives so special especially for Mac Users.

To Trim Or Not To Trim? That Is The Question?

As many of you know I have a Mac Pro cheesegrater and for two years I have been using a Crucial M4 512G SSD drive as my boot drive. However I have not enabled the TRIM function on it for a number of reasons.  

1. The nasty warnings you get about potential data lose if you enable TRIM. 
2. Opening up the security of my Mac.  With OS X 10.10 Yosemite, Apple introduced “kext signing” short for Kernel EXTension signing. This makes sure that all the drivers on a Mac are either left unchanged or they are approved by Apple. As TRIM-enabling utilities need to work at this low level, it means they were not modifiable unless you are prepared to disable the kext signing security mechanism to enable TRIM for these drives, and therefore reducing a Mac’s security. However starting with OS X 10.10.4, Apple now provides an official but yet unsupported way of enabling TRIM for any SSD without having to compromise the security of your Mac.
3. Not all TRIM commands are the same. Different SSD drives have different protocols for the TRIM function. What this can mean is that if you enable the TRIM function on Mac OS 10.10 and above, it can only issue the Apple protocol for the TRIM command. Other brands may misinterpret this command and delete wanted data rather than unwanted data. The consequences of this can be huge data lose.

So I asked Crucial about whether I could or should use the TRIM function on my M4 drive. This was their response...

I do not normally recommend enabling the Force Trim command, as this can potentially corrupt or damage data being stored on the drive.  As the M4 has built-in garbage collection, TRIM is not necessary for the drive to maintain performance.  In order to activate the built-in clean up, all you need to do is restart the computer while holding down the 'Options' key.  This brings you to the Boot Manager screen, where you will leave the system for a period of 6-8 hours (typically overnight is the recommended time).  This procedure gives the drive idle power, which allows the controller to activate the Active Garbage Collection.  The Garbage Collection will clean up any invalid data being stored on the drive.  This sequence should only need to be done once every 2-3 months, depending on usage and writes performed on the drive.

So my advice to all Mac Yosemite users is NOT to enable the Force Trim command unless you have either an Apple or Angelbird SSD drive. For this reason I wanted to get an Angelbird drive as I was noticing a slow down in the performance of my Mac Pro which could be attributed to the lack of TRIM or Garbage Collection going on.

But Why Is TRIM So Important?

When the OS, (Mac, Windows or Linux) uses TRIM with a solid-state drive, it sends a signal to the SSD every time you delete a file. The SSD then knows that the file is deleted and it can erase the file’s data from its flash storage.  Nothing special there then, after all that is how rotational drives work. They don't actually delete the file, they tell the system that the space that was occupied by the 'deleted' file is now available for reuse and so can be overwritten. Unerase type apps depend on this fact so that if you should delete a file in error you should resolve that asap. The longer you leave it the less likely it will be possible to recover the file.

With flash memory, it’s actually faster to write to empty memory than to write to full memory, which means that the memory should first be erased and then written to. This causes your SSD to slow down over time unless TRIM is enabled. TRIM ensures the physical NAND memory locations containing deleted files are erased before you need to write to them. The SSD can then manage its available storage more intelligently.  So this could be why my Mac Pro was slowing down because I wasn't using TRIM on it. There is also some debate as to whether Garbage Collection on its own is sufficient to keep an SSD drive in tip top condition. So all in all I needed an Angelbird SSD drive for my Mac Pro as you cannot buy Apple SSD drives separately. You can order your Mac to have one fitted when you buy it, but it isn't possible to retro fit Apple SSD drives afterwards.

In Part 2...

I will review the Angelbird SSD wrk for Mac Pro and see if it lives up to my hopes and expectations.