Get machine free memory both on Mac OS and Linux.

get_free_memory

#!/usr/bin/python

# Author: Wubin Qu <quwubin@gmail.com>
# Tue Jan 28 23:17:08 2014

import platform
import subprocess
import re

def get_free_memory():
    if platform.system() == 'Darwin':
        # Get process info
        vm = subprocess.Popen(['vm_stat'], stdout=subprocess.PIPE).communicate()[0]
        installed_memory = float(subprocess.Popen(['sysctl', '-n', 'hw.memsize'], stdout=subprocess.PIPE).communicate()[0])

        # Process vm_stat
        vmLines = vm.split('\n')
        sep = re.compile(':[\s]+')
        vmStats = {}
        for row in range(1,len(vmLines)-2):
            rowText = vmLines[row].strip()
            rowElements = sep.split(rowText)
            vmStats[(rowElements[0])] = int(rowElements[1].strip('\.')) * 4096

        total_comsumed = vmStats["Pages wired down"] + vmStats["Pages active"] + vmStats["Pages inactive"]

        return (installed_memory - total_comsumed) / installed_memory * 100

    elif platform.system() == 'Linux':
        items = subprocess.Popen(['free', '-m'], stdout=subprocess.PIPE).communicate()[0].splitlines()[1].strip().split()
        free = float(items[3]) + float(items[5]) + float(items[6])
        total = float(items[1])

        return free / total * 100
    else:
        print "Sorry, currently only support Mac OS and Linux."
        return 0



print get_free_memory()