Synnefo

#!/usr/bin/env python

import os

import collectd

from glob import glob

def get_vcpus(pid):

    """Get a KVM instance vCPU count by looking at its fd's"""

    vcpus = 0

    for fd in glob("/proc/%d/fd/*" % pid):

        # XXX: sad but trueeeeeeeeeeee

        if os.readlink(fd) == "anon_inode:kvm-vcpu":

            vcpus += 1

    return vcpus

def cpustats(data=None):

    for file in glob("/var/run/ganeti/kvm-hypervisor/pid/*"):

        instance = os.path.basename(file)

        try:

            pid = int(open(file, "r").read())

            proc = open("/proc/%d/stat" % pid, "r")

            cputime = [int(proc.readline().split()[42])]

        except EnvironmentError:

            continue

        vcpus = get_vcpus(pid)

        proc.close()

        vl = collectd.Values(type="derive")

        vl.host = instance

        vl.plugin = "cpu"

        vl.type = "virt_cpu_total"

        total = sum(cputime) * 100 / (vcpus * os.sysconf("SC_CLK_TCK"))

        vl.dispatch(values=[total])

collectd.register_read(cpustats)

# vim: set ts=4 sts=4 et sw=4 :