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

Detecting Block Device Performance Bottlenecks with lsblk

🧩 The Challenge

You need to identify which disks are currently performing heavy I/O operations without installing heavy monitoring suites.

💡 The Fix

Use the specific column filtering capability of lsblk to display active request queues and current I/O pressure metrics.

lsblk -o NAME,SIZE,TYPE,MOUNTPOINT,RQ-SIZE,RA-AHEAD,SCHED

⚙️ Why It Works

The RQ-SIZE column shows the size of the request queue, helping you visualize pending operations, while the SCHED column reveals the I/O scheduler currently managing that specific device.

🚀 Pro-Tip: Append -e 7 to the command to exclude loop devices and keep your output focused solely on physical disks and partitions.

Linux Tips & Tricks | © ngelinux.com | 7/11/2026