Find and delete all but N largest files in 100s of directories

Question

I have 100s of sibling directories on a BSD/Unix system, each with a collection of files in it. I'd like to delete all but the N largest files in each directory. (N is 5 for me.)

Assuming that I can use some 'find' magic for this, but not quite sure how.

Answer 1

Try running this command, I think you'll like it

find /path/to/dir -type f -print0 | xargs -0 du -s | sort -rn | awk 'NR>5 {print $NF}' | xargs rm -f

This will print all files underneath the /path/to/dir directory, compute the size of each file, sort by size, extract out the names of all (except the top 5) files, and pass that to rm.

To perform this on each directory individually, you're better off wrapping it in a script, like

#!/bin/bash

for DIR in `find /path -maxdepth 1 -type d`
do
    find ${DIR} -type f -print0 | xargs -0 du -s | sort -rn | awk 'NR>5 {print $NF}' | xargs rm -f
done

Where /path is the parent directory that contains all of your sibling directories. This will accomplish the same thing that @TomNewton describes by individually executing the workflow on each sibling directory.