Crucial SSDs have a maintenance feature called Active Garbage Collection built into the controller of the SSD. Active Garbage Collection does background clean-up on the drive and runs when the SSD has power but is not actively reading or writing data. The purpose of this feature is to maintain the SSD's performance in environments where TRIM (discussed here) is not functioning normally.
In order for Active Garbage Collection to have an effect, the SSD needs to have periods of idle time. If the SSD is not given any idle time (ie: constant data transfers), then Active Garbage Collection will never be triggered. The drive must also have empty space available, since TRIM and Active Garbage Collection both rely on the ability to move data between sectors as a part of the clean-up . For best results, keeping at least 10% of your SSD clear ensures this process runs optimally.
An SSD that is not receiving TRIM commands and where Active Garbage Collection never runs properly, will never have the cells on the drive cleaned out after data is deleted. Over time, this will lead to an accumulation of 'junk' data, which will reduce performance and can cause system freezing.
If you notice performance decreasing on the SSD, you may need to force Active Garbage Collection to run by powering the SSD on and leaving it idle for 6 to 8 hours. After that, your drive’s functionality and performance should be restored.
Follow these steps to trigger Active Garbage Collection on your Crucial SSD:
On a PC, power on with the SSD installed and enter your system's BIOS or UEFI (please refer to your system manufacturer’s documentation on how to access the BIOS.) Leave the system in this menu for 6-8 hours, which will power the SSD but not execute any operations, allowing Garbage Collection to run.
On a Mac, hold down the Options key while powering on to enter the Startup Manager screen. Leaving the Mac on that screen provides the SSD with power but keeps it in an idle state so Garbage Collection can function, just like the BIOS or UEFI on a Windows laptop.
To prevent the SSD performance from degrading again in the future you can adjust your power settings to ensure the SSD stays powered on when your computer goes into sleep mode, which will allow Garbage Collection to run.
- Go to Control Panel - Go to Hardware and Sound - Go to Power Options - Select Change Plan Settings - Select Change Advanced Settings - Make sure the 'hard disk' field is set to ‘never’ (Laptop users select 'battery and power adapter').
On a Mac computer:
- Go to System Preferences - Go to Energy Saver - Make sure 'Put the hard disk(s) to sleep when possible' is unchecked.