gentextfiles.py

#!/usr/bin/env python3

import os
import random
import string

# With these settings, it took me 12 minutes to generate. YMMV.
dirs = 10
sublevels = 10
files = 10
filesize = 1024  # in kB
root = '/var/tmp/dirtest'
chars = string.printable

def genData():
    for d in range(dirs):
        base = os.path.join(os.path.abspath(root), str(d))
        for s in range(sublevels):
            path = os.path.join(base, str(s))
            os.makedirs(path, exist_ok = True)
            for f in range(files):
                fpath = os.path.join(path, str(f))
                with open(fpath, 'a') as fh:
                    fh.write(''.join(random.choice(chars) for i in range((filesize * 1024))))

genData()