#!/usr/bin/env python3

from time import sleep, time

t0 = time()

hog_list = []

duration = 60

sff_max = 0.55
sff_min = 0.45

mb = 1024 * 1024
path = '/dev/zero'

def sff():
    """
    SwapFree fraction
    """
    with open('/proc/meminfo') as f:
        for i in f:
            if i.startswith('SwapTotal'):
                st = i.split(':')[1].strip(' kB\n')
            if i.startswith('SwapFree'):
                sf = i.split(':')[1].strip(' kB\n')
                st = float(st) + 1
                sf = float(sf)
                return sf / st


def hog(hog_list):
    """
    """
    with open(path, 'rb') as f:
        raw = f.read(mb)
        hog_list.append(raw)

    return hog_list


while True:

    while sff() > sff_min:
        hog_list.reverse()
        if time() - t0 > duration:
            exit()
        hog_list = hog(hog_list)
        print('MiB:', len(hog_list), 'SwapFree:', sff(), 'time:', time() - t0)

    while sff() < sff_max:
        hog_list.reverse()
        if time() - t0 > duration:
            exit()
        try:
            hog_list.pop()
        except IndexError:
            break
        print('MiB:', len(hog_list), 'SwapFree:', sff(), 'time:', time() - t0)