fix(ansible): optimize root trim policy

Co-authored-by: Junie <junie@jetbrains.com>
2026-04-02 16:15:32 +02:00
parent bbdcd43e01
commit 6ff790fd4b
3 changed files with 116 additions and 0 deletions
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+---
+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