SSD TRIM

TRIM lets an SSD know which blocks are no longer in use, so the controller can erase them in advance instead of during a later write. Without it, write performance degrades over time as the drive runs out of pre-erased blocks.

There are two ways to issue TRIM commands, and you only need one of them.

Method	How it works	Status on ParrotOS
Periodic (fstrim.timer)	A weekly systemd timer trims all mounted filesystems at once	Enabled by default
Continuous (discard)	The kernel sends a TRIM command on every file deletion	Off by default

Periodic TRIM is the recommended approach and is already active, so in most cases there is nothing to configure. Continuous TRIM adds latency to every delete operation and, on some older drives, degrades performance instead of improving it.

Check That Your Drive Supports TRIM

List your drives and their discard capabilities:

┌─[user@parrot]─[~]
└──╼ $ lsblk --discard

If the DISC-GRAN and DISC-MAX columns show non-zero values, the device supports TRIM:

NAME        DISC-ALN DISC-GRAN DISC-MAX DISC-ZERO
nvme0n1            0      512B       2T         0
├─nvme0n1p1        0      512B       2T         0
└─nvme0n1p2        0      512B       2T         0

A value of 0B in both columns means the drive does not advertise TRIM support, and neither method below will have any effect.

Note

hdparm -I also reports TRIM support, but only for SATA devices. lsblk --discard works for SATA and NVMe alike, so prefer it.

Periodic TRIM (Recommended)

Check that the timer is active:

┌─[user@parrot]─[~]
└──╼ $ systemctl status fstrim.timer

If it is not enabled, enable it:

┌─[user@parrot]─[~]
└──╼ $ sudo systemctl enable --now fstrim.timer

You can inspect when it last ran and when it will run next:

┌─[user@parrot]─[~]
└──╼ $ systemctl list-timers fstrim.timer

To trim every mounted filesystem immediately, without waiting for the timer:

┌─[user@parrot]─[~]
└──╼ $ sudo fstrim --all --verbose

Continuous TRIM (Optional)

Only configure this if you have a specific reason to prefer it over the timer. Do not enable both: running discard alongside fstrim.timer provides no benefit.

Back up your fstab first

A malformed /etc/fstab can leave the system unable to boot. Make a copy before editing it.

┌─[user@parrot]─[~]
└──╼ $ sudo cp /etc/fstab /etc/fstab.bak

Open the file:

┌─[user@parrot]─[~]
└──╼ $ sudo nano /etc/fstab

Locate the line for the filesystem you want to trim. A root ext4 entry looks like this:

UUID=1cd2fc4f-7d99-4c7a-8ea7-6f9a2d5e5960  /  ext4  errors=remount-ro  0  1

Note

The UUID above is only an example. Use the one already present in your own file, and leave the last two numeric fields untouched.

Add discard to the comma-separated options field, keeping every other option intact:

UUID=1cd2fc4f-7d99-4c7a-8ea7-6f9a2d5e5960  /  ext4  discard,errors=remount-ro  0  1

Verify that the file still parses correctly before rebooting:

┌─[user@parrot]─[~]
└──╼ $ sudo findmnt --verify --verbose

Apply the new options without a reboot:

┌─[user@parrot]─[~]
└──╼ $ sudo mount -o remount /

If fstrim.timer is enabled, disable it now that TRIM is handled at mount level:

┌─[user@parrot]─[~]
└──╼ $ sudo systemctl disable --now fstrim.timer