while read inum rest; do
    mkdir -p /mnt/recovered/apr29/${inum}
    python3 dump_tree.py ${inum} /mnt/recovered/apr29/${inum}/ &
    # Limit to 10 parallel jobs
    while (( $(jobs -r | wc -l) >= 4 )); do
        wait -n 2>/dev/null || sleep 0.2
    done
done < true_roots.txt
wait
echo "All done"