---
description: >-
  TRIM policy optimization for the mw-pfeddersheim-workstation after the
  Samsung PM9A1 firmware update to GXA7801Q.
tags:
  - storage
  - trim
  - nvme
  - ansible
  - optimization
last_updated: '2026-04-02'
---

# TRIM Optimization After PM9A1 Firmware Update

## Summary

On 2026-04-02 the workstation TRIM policy was aligned with current Linux best
practice for ext4.

- Root filesystem (`/`) on `/dev/nvme0n1p2` was changed from `noatime,discard`
  to `noatime` in `/etc/fstab`
- Weekly `fstrim.timer` remains enabled and active
- Continuous ext4 discard was disabled at runtime with a remount using
  `nodiscard`

## Why This Change Was Necessary

The root ext4 filesystem was configured with continuous `discard` while the
system already had periodic TRIM enabled via `fstrim.timer`.

For ext4, continuous discard adds overhead to unlink and truncate operations.
With a healthy weekly `fstrim.timer`, it is redundant on this workstation.

## Implementation

The persistent change was implemented in Ansible.

- `ansible/vars/main.yml`
  - added `root_filesystem_uuid`
  - added `root_filesystem_mount_opts: noatime`
- `ansible/roles/common/tasks/main.yml`
  - ensured the root fstab entry is managed with `mount: state=present`
  - checked current root mount options with `findmnt`
  - remounted `/` without continuous discard when needed

## Verification

### fstab

```text
UUID=2aeade2e-b169-4964-8cbd-bb7356320b51 / ext4 noatime 0 1
```

### Periodic TRIM

```text
ActiveState=active
UnitFileState=enabled
NextElapseUSecRealtime=Mon 2026-04-06 00:49:28 CEST
```

### Validation Steps

```text
ansible-playbook ansible/workstation.yml --check --tags trim
ansible-playbook ansible/workstation.yml --tags trim
findmnt --verify --tab-file /etc/fstab
```

## Notes

- `/boot/efi` remains unchanged
- This change only targets the ext4 root filesystem TRIM policy
- Firmware and benchmark documentation remain in the NVMe benchmark documents