Disk & Filesystem Management (Du/Df/Lsblk/Fstrim)

Reclaim SSD health before your cloud provider throttles your I/O

🧩 The Challenge

You ever notice your database performance crater after a few months on a cloud VM, only to realize the underlying SSD is choked with stale data that the OS doesn’t know is free? It’s a total pain because your monitoring shows plenty of space, but the controller is dying inside trying to manage the garbage collection.

💡 The Fix

Run a manual discard pass on your filesystems to explicitly tell the drive which blocks are actually empty. This clears out the bloat and brings your write speeds back to what they were on day one.

fstrim -av

⚙️ Why It Works

Discard commands allow the filesystem to communicate with the flash controller, effectively mapping out dead blocks so the drive can stop moving useless data around during write cycles.

🚀 Pro-Tip: Throw this into a weekly cron job and stop thinking about it entirely.

Linux Tips & Tricks | © ngelinux.com | 10/20/2026