Fast Alternatives to du: ncdu, dust, duu, diskus, and tin‑summer on Linux

Why replace du?

The traditional du command can become very slow on large or nearly‑full filesystems. Modern replacements written in C or Rust provide faster, interactive output and additional filtering options.

ncdu

ncdu is a lightweight ncurses‑based disk‑usage analyzer written in C.

Installation (Ubuntu 21.10) # sudo apt-get install ncdu Basic usage ncdu [directory] Run ncdu in a directory to open an interactive UI. Use the arrow keys to navigate, Enter to drill down, d to delete a selected entry, and q to quit.

Common options -h – show help -q – quiet mode (refresh every 2 s) -v – version -x – stay on the same filesystem -e – enable extended info -r – read‑only -o FILE – export scan to a file -f FILE – import scan from a file --si – use decimal SI prefixes --exclude PATTERN – exclude matching files -X, --exclude-from FILE – exclude patterns listed in a file -L, --follow-symlinks – follow symlinks (files only) --exclude-caches – skip directories containing

CACHEDIR.TAG

--exclude-kernfs

– skip kernel pseudo‑filesystems (procfs, sysfs, cgroup…) --confirm-quit – ask for confirmation before exiting --color SCHEME – set colour scheme

dust

dust (du + Rust) provides a more intuitive, colourised output and supports file‑type filtering.

Installation (Ubuntu 21.10)

# wget https://github.com/bootandy/dust/releases/download/v0.7.1/du-dust_0.7.1_amd64.deb
# dpkg -i du-dust_0.7.1_amd64.deb

Basic usage dust [FLAGS] [OPTIONS] [--] [inputs]... Key flags -f – show file count instead of size -s – use file length rather than block size -p – display full paths --exclude PATTERN – exclude matching files

duu

duu (Directory Usage Utility) is a cross‑platform Python script that reports sizes in kilobytes.

Installation (Ubuntu 21.10)

# wget https://github.com/jftuga/duu/archive/refs/tags/v2.22.tar.gz
# tar -zxvf v2.22.tar.gz
# cd duu-2.22
# python3 duu.py --help

Typical usage

# python3 duu.py               # current directory
# python3 duu.py /etc/init.d/   # specific path

Common options -h – help -b – suppress summary/statistics (useful for sorting) -e – summarise file extensions -q – quiet (do not list individual directories) -s – send processing status to STDERR -n – skip hidden directories (starting with .) -N – non‑recursive -f – show file count per directory -S – show mean, median, mode and standard deviation -H – human‑readable numbers -T THREADS – number of concurrent threads (useful on SAN) -x EXCLUDE – case‑insensitive exclude list (colon‑separated) -X REGEXPR – case‑insensitive regex exclude list -o OUTPUT – write results to CSV

diskus

diskus is a Rust‑based tool that aims to replace du -sh with multithreaded performance.

Installation (Ubuntu 21.10)

# wget https://github.com/sharkdp/diskus/releases/download/v0.7.0/diskus_0.7.0_amd64.deb
# dpkg -i diskus_0.7.0_amd64.deb

Basic usage diskus [OPTIONS] [path]... Important options -j – set thread count and output unit (default: 3 × cores, decimal MB) -b – compute apparent size instead of disk usage -v – show version / do not hide filesystem errors -h – help

Examples

# du -sh /etc               # traditional du
# diskus /etc               # diskus equivalent
# diskus -j8 -b /var        # use 8 threads, apparent size

Benchmark (15 GB folder, 100 k directories, 400 k files) on an 8‑core laptop using hyperfine

Cold cache (mean ± σ, seconds):

Command          Mean   Min   Max   Relative
------------------------------------------------
 diskus          1.746  1.728 1.770 1.00
 du -sh          17.776 17.139 18.413 10.18
 sn p -d0 -j8    18.094 17.482 18.579 10.36
 dust -d0        21.357 20.974 21.759 12.23

Hot cache (mean ± σ, seconds):

Command          Mean    Min    Max   Relative
------------------------------------------------
 diskus          500.3   472.9  530.6   1.00
 du -sh         1098.3 1087.8 1122.4   2.20
 sn p -d0 -j8   1122.2 1107.3 1170.1   2.24
 dust -d0       3532.1 3490.0 3563.1   7.06

tin‑summer (sn)

tin‑summer, invoked as sn, is a Rust‑based du replacement that reads file sizes (not allocated blocks) and offers colourised, human‑readable output with multithreading.

Installation

# curl -LSfs https://japaric.github.io/trust/install.sh | sh -s -- --git vmchale/tin-summer
# or, if Rust is installed:
# cargo install tin-summer

Typical commands sn f – list file sizes in the current directory sn f <path> – list sizes for a specific directory sn ar – search for build artefacts sn ar -t200M – list items larger than 200 MiB sn sort $DIR -n12 – show the 12 largest entries in $DIR Benchmark (selected directory sizes)

Directory   Tool   Command   Time (ms)
-----------------------------------
600 MB      sn     sn p      60.74
600 MB      sn     sn d      99.92
600 MB      du     du -hacd2 88.28
4 GB        sn     sn p     185.2
4 GB        sn     sn d     271.9
4 GB        du     du -hacd2 195.5
700 MB      sn     sn p      91.05
700 MB      sn     sn d     176.3
700 MB      du     du -hacd2 153.8
7 MB        sn     sn p      19.48
7 MB        sn     sn d      12.72
7 MB        du     du -hacd2 10.13

References

dust: https://github.com/bootandy/dust/

duu: https://github.com/jftuga/duu

diskus: https://github.com/sharkdp/diskus/

tin‑summer (sn): https://github.com/vmchale/tin-summer