Master Linux Disk Usage: Essential Commands to Monitor and Manage Filesystems

The article presents a collection of concise Linux command‑line snippets useful for inspecting, sorting, and monitoring disk usage and filesystem information.

Sort directories or files by size and display the top 15 entries: du -xB M --max-depth=2 /var | sort -rn | head -n 15 List the size of all immediate subdirectories: du -h --max-depth=1 Show the ten largest files or directories in the current location: du -s * | sort -n | tail Sort directories by size in descending order with human‑readable units:

du -b --max-depth 1 | sort -nr | perl -pe 's{([0-9]+)}{sprintf "%.1f%s", $1>=2**30?($1/2**30,"G"):$1>=2**20?($1/2**20,"M"):$1>=2**10?($1/2**10,"K"):( $1, "")}e'

Display a sorted file tree for a specific path: du -h /path | sort -h Monitor size changes of a directory every 60 seconds: watch -n60 du /var/log/messages Recursively delete all .svn directories under the current directory: find . -type d -name '.svn' -print0 | xargs -0 rm -rdf Show overall disk usage in a column‑aligned format: df -P | column -t Continuously monitor disk usage every 5 seconds: watch -d -n 5 df Display inode usage for a specific partition: df -i <partition> Sort disks by usage percentage (high to low):

df -h | grep -v ^none | (read header; echo "$header"; sort -rn -k 5)

Show physical disk usage while excluding temporary filesystems and common virtual mounts: df -x tmpfs | grep -vE "(gvfs|procbususb|rootfs)" Display total size and usage of all disks in human‑readable format: df -H List all partitions on a device: fdisk -l /dev/sda Show sector counts instead of cylinder numbers: fdisk -u Display block count for a specific partition: fdisk -s partition Check read/write throughput of a disk: iostat -m -d /dev/sda1 Test raw read speed of a disk: hdparm -t /dev/sda Find all hard links pointing to a given file: find -L / -samefile /path/to/file -exec ls -ld {} + List the five largest files in the current directory tree: find . -type f -exec ls -s {} \; | sort -n -r | head -5 Delete files older than 365 days: find ./ -type f -mtime +365 -exec rm -f {} \; Find files larger than 100 MiB:

find . -type f -size +100M