test_random_access.py

import argparse
import os
import random

parser = argparse.ArgumentParser()
parser.add_argument('file')
args = parser.parse_args()

data = []
read_size = 1024 * 4

with open(args.file, "rb") as in_file:
        in_file.seek(0, os.SEEK_END)
        size = in_file.tell()
        print('File size:', size, 'Read size:', read_size)
        for i in range(8000):
                pos = random.randrange(size - read_size)
                in_file.seek(pos, os.SEEK_SET)
                data.append(in_file.read(read_size))

print(sum([ len(page) for page in data]), 'bytes read')