Dirscan 
Dirscan is a high-performance tool for quickly inspecting the contents of large disks. It provides a summary of every single directory on a given disk, complete with the number of files within, their total size, and the latest time a file was created, accessed or modified.
It is significantly faster than tools like ncdu, and produces a simple JSON or CSV output that can be analysed by the
built-in viewer or loaded into other tools.
Table of Contents
Install :cd:
Homebrew (MacOS + Linux)
brew tap orf/brew, then brew install dirscan
Binaries (Windows)
Download the latest release from the github releases page. Extract it
and move it to a directory on your PATH.
Cargo
For optimal performance run cargo install dirscan
Usage :saxophone:
Scan a directory
You can start scanning a directory by executing:
dirscan scan [PATH] --output=[OUTPUT]
This will scan [PATH] and output all results, in JSON format, to [OUTPUT]. By default it will use a thread pool with
2 * number_of_cores threads, but you can customize this. Depending on your disk speed the number of threads can
drastically improve performance:
dirscan scan [PATH] --output=[OUTPUT] --threads=20
You can also output the results in CSV:
dirscan scan [PATH] --output=[OUTPUT] --format=csv
Inspect results
Once a scan is complete you can inspect the output using:
dirscan parse [OUTPUT]
For example:
$ dirscan parse output.json --prefix=/System/
[00:00:02] Total: 580000 | Per sec: 220653/s
+----------------------+---------+----------+-------------+-------------+-------------+
| Prefix | Files | Size | created | accessed | modified |
+----------------------+---------+----------+-------------+-------------+-------------+
| /System/Applications | 57304 | 777.28MB | 2 weeks ago | 2 weeks ago | 2 weeks ago |
| /System/DriverKit | 55 | 5.09MB | 2 weeks ago | 2 weeks ago | 2 weeks ago |
| /System/Library | 292190 | 13.56GB | 7 hours ago | 1 hour ago | 7 hours ago |
| /System/Volumes | 1468296 | 197.93GB | 1 hour ago | 1 hour ago | 1 hour ago |
| /System/iOSSupport | 13856 | 600.20MB | 2 weeks ago | 2 weeks ago | 2 weeks ago |
+----------------------+---------+----------+-------------+-------------+-------------+
You can include more directories with the --depth flag, or change the prefix search with --prefix.