sge load sensor for nvidia gpgpus

#!/usr/bin/python

import subprocess
from xml.etree import ElementTree
from sys import stderr

try:
    p = subprocess.Popen(["uname", "-n"],
        stdout=subprocess.PIPE,
        stderr=subprocess.STDOUT)
    p.wait()
    hostname = p.communicate()[0].strip()
except:
    print >> stderr, "Oops. Couldn't determine my hostname using `uname`"
    exit(1)

def getUnoccupiedGPUCount():
    result = 0
    try:
        p = subprocess.Popen(["nvidia-smi", "-q", "-x"],
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT)
        p.wait()
        xmlt = ElementTree.XML(p.communicate()[0])
        for gpu in xmlt.getiterator(tag="gpu"):
            if len(gpu.find("compute_processes").getchildren()) < 1:
                result += 1
    except:
        result = 0
        print >> stderr, "Oops. Something went wrong, when I tried reading from nvidia-smi. I will exit now!"
        exit(1)
    return result

while(True):
    cmd = ""
    try:
        cmd = raw_input()
    except:
        pass

    if cmd == "quit":
        exit()

    print "begin\n"+hostname+":gpu:"+str(getUnoccupiedGPUCount())+"\nend"