dirspeed.py

#!/usr/bin/env python3

from pathlib import Path
import time
import sys

dirpath = sys.argv[1]

def fsize(f):
    try:
        return f.stat().st_size
    except:
        return 0

def sum_dir(path):
    while True:
        try:
            return sum(fsize(file) for file in Path(path).rglob('*'))
        except: pass

def pretty_size(size):
    sz = abs(size)
    if sz > 1024 * 1024 * 1024:
        return f"{size / (1024 * 1024 * 1024)} GiB"
    elif sz > 1024 * 1024:
        return f"{size / (1024 * 1024)} MiB"
    elif sz > 1024:
        return f"{size / 1024} kiB"
    else:
        return f"{size} B"

def calc_rate(duration, delta_size):
    bps = delta_size / duration
    return f"{pretty_size(bps)}/s"

prev_size = sum_dir(dirpath)
prev_time = time.time()
print(pretty_size(prev_size))
while True:
    time.sleep(4)
    size = sum_dir(dirpath)
    t = time.time()
    print(pretty_size(size), calc_rate(t - prev_time, size - prev_size))
    prev_size = size
    prev_time = t