m.sh

!/bin/bash

set -eu

m1000() {
	for i in $(seq 100) ; do 
		D=mtest.$BASHPID.$i/foo/bar/baz
		mkdir -p $D
		touch $D/foo $D/bar
		echo AAAAAAAAAAAAAAAAAAAAA > $D/foo
		rm $D/foo
		mkdir $D/baz
	done
}

rm -Rf mtest.*
echo .

m1000 &
m1000 &

wait