Enable TRIM for Third-Party SSDs on Mac OS X

Enabling TRIM Support for Aftermarket SSDs on Macs

Apple’s operating systems historically only activated the TRIM function for solid-state drives (SSDs) that were originally installed during the Mac’s manufacturing process.

Consequently, if a user installs a third-party or aftermarket SSD to upgrade their Mac, the TRIM command is not automatically utilized.

The Impact of Disabling TRIM

The absence of TRIM support can lead to a gradual decline in the SSD’s performance over time. This is because TRIM helps maintain optimal write speeds.

TRIM Support Introduced in Mac OS X 10.10.4

With the release of Mac OS X 10.10.4, Apple introduced a method for enabling TRIM on any SSD installed in a Mac.

This is achieved through a straightforward command-line instruction, simplifying the process significantly.

Simplified TRIM Activation

Previously, enabling TRIM on aftermarket SSDs required users to compromise the security settings of their operating system and make alterations to the core system files.

The new method eliminates the need for these complex and potentially risky procedures.

Benefits of Enabling TRIM

• Maintains optimal SSD write performance.
• Extends the lifespan of the SSD.
• Improves overall system responsiveness.

By utilizing this command, Mac users can now ensure that their aftermarket SSDs operate at peak efficiency, mirroring the performance of Apple-supplied drives.

The Significance of TRIM and its Default Status on macOS

Related: Understanding SSD Performance Degradation with Capacity

The TRIM function is crucial when utilizing a solid-state drive (SSD). It allows the operating system to communicate with the SSD, signaling when a file has been deleted. This notification enables the SSD to proactively erase the corresponding data from its flash memory.

Writing data to empty blocks within flash memory is significantly faster than writing to blocks that require prior erasure. Without TRIM, SSD performance can degrade over time as the drive fills up. TRIM optimizes performance by ensuring that NAND memory locations previously occupied by deleted files are cleared before new data is written.

Windows operating systems, beginning with version 7, include native TRIM support and automatically activate it for all connected SSDs. Conversely, macOS has historically limited TRIM functionality to SSDs manufactured and installed by Apple themselves.

Users upgrading their Macs with third-party SSDs previously needed to rely on unofficial tools to enable TRIM. However, these tools operated at a low system level.

The introduction of kernel extension signing in OS X 10.10 Yosemite altered this landscape. This security feature verifies the integrity of system drivers, effectively blocking many TRIM-enabling utilities. Disabling kext signing was required to use these utilities, potentially compromising system security.

Beginning with OS X 10.10.4, Apple introduced an officially sanctioned, though unsupported, method for activating TRIM on any SSD. This provided a more secure alternative to relying on third-party solutions.

How TRIM Benefits SSD Performance

• Faster Write Speeds: TRIM allows the SSD to maintain optimal write performance.
• Reduced Wear Leveling: By proactively erasing blocks, TRIM contributes to more efficient wear leveling.
• Consistent Performance: TRIM helps prevent the performance slowdowns that can occur as an SSD becomes full.

Assessing the Safety of Enabling TRIM for SSDs

The safety of activating TRIM functionality is contingent upon the specific SSD utilized within your Mac system. Apple exercises caution and avoids assuming liability for potential problems. Consequently, the operating system conceals this feature behind a command-line interface accompanied by a cautionary message.

Each solid-state drive employs a unique implementation of TRIM. Many manufacturers primarily conduct compatibility testing within a Windows environment. Algolia, a search technology company, identified data corruption vulnerabilities affecting specific Samsung SSDs when TRIM was enabled on Linux. Comparable issues could potentially arise if TRIM were activated for such drives on a Mac.

Reports have also surfaced indicating functional inconsistencies with certain Crucial drives when TRIM is utilized on Linux systems. The Linux kernel maintains a list of SSDs that exhibit improper TRIM support. Activating trimforce is generally discouraged if your drive is listed on this blacklist within your Mac.

However, a majority of drives appear to function correctly with TRIM enabled on macOS. Mac users have consistently employed third-party TRIM-enabling tools for numerous years, across a diverse range of SSDs. Prior to proceeding, it is advisable to investigate the experiences of other Mac users who have enabled TRIM with your particular SSD model.

Considerations Before Enabling TRIM

• Manufacturer Testing: Determine if your SSD manufacturer has thoroughly tested TRIM compatibility with macOS.
• Linux Blacklist: Check if your SSD is present on the Linux kernel's TRIM incompatibility blacklist.
• User Reports: Research online forums and communities for feedback from other Mac users with the same SSD.

Enabling TRIM can enhance SSD performance and longevity, but it's crucial to assess potential risks beforehand. Proper research and understanding of your drive's compatibility are essential for a safe and optimal experience.

Activating TRIM using trimforce

A new command, "trimforce," was introduced by Apple in a subtle update to OS X 10.10 Yosemite – specifically, version 10.10.4. This utility is also present within OS X 10.11 El Capitan.

This command functions by activating TRIM across all SSDs installed in your Mac. It bypasses the standard verification process that previously restricted TRIM functionality to solid-state drives originally provided by Apple. Once executed, TRIM will be universally enabled for every solid-state drive connected to the system. It’s important to note that enabling TRIM via this method is an all-or-nothing process; it cannot be selectively applied to individual drives.

Caution: Proceed at your own discretion! Maintaining current backups of your crucial data is always recommended, as a precautionary measure.

To utilize trimforce, launch a Terminal window. This can be achieved by pressing Command + Space, typing "Terminal," and then pressing Enter to initiate the application through Spotlight. Enter the following command into the terminal and press Enter:

sudo trimforce enable

You will be prompted to enter the password associated with your user account. Following this, a warning message will appear, requiring confirmation by typing y to proceed.