How to get memory usage of an external program - python

Question

I am trying to get the memory usage of an external program within my python script. I have tried using the script http://code.activestate.com/recipes/286222/ as follows:

m0 = memory()
subprocess.call('My program')
m1 = memory(m0)
print m1

But this seems to be just giving me the memory usage of the python script rather than 'My program'. Is there a way of outputting the memory usage of the program for use within the python script?

Answer 1

Try using Psutil

import psutil
import subprocess
import time

SLICE_IN_SECONDS = 1
p = subprocess.Popen('calling/your/program')
resultTable = []
while p.poll() == None:
  resultTable.append(psutil.get_memory_info(p.pid))
  time.sleep(SLICE_IN_SECONDS)

Answer 2

If you look at the recipe you will see the line:

_proc_status = '/proc/%d/status' % os.getpid()

I suggest you replace the os.getpid() with the process id of your child process. As @Neal said, as I was typing this you need to use Popen and get the pid attribute of the returned object.

However, you have a possible race condition because you don't know at what state the child process is at, and the memory usage will vary anyway.