Python testing WMI

testwmi.py

#pip install comtypes wmi
import sys, os, traceback
sys.coinit_flags = 0 # sets pythoncom.COINIT_MULTITHREADED = 0
import comtypes.client # http://starship.python.net/crew/theller/comtypes/
from comtypes.automation import IDispatch, IEnumVARIANT
import wmi

#Use help(...) and dir(...) on any object/class to see more details

#These are already set on the main thread by sys package, but need to call if we use other threads
#comtypes.CoInitializeEx(comtypes.COINIT_MULTITHREADED)

def GetMemoryUsageMB():
    w = wmi.WMI('.')
    result = w.query("SELECT WorkingSetPrivate FROM Win32_PerfRawData_PerfProc_Process WHERE IDProcess="+str(os.getpid()))
    subset = result[0]
    return float(subset.WorkingSetPrivate)/1024./1024.

print "Start %.2fMB" % GetMemoryUsageMB()

progid = "WbemScripting.SWbemLocator"
clsid = comtypes.GUID.from_progid(progid)
clsctx = comtypes.CLSCTX_INPROC_SERVER | comtypes.CLSCTX_LOCAL_SERVER | comtypes.CLSCTX_REMOTE_SERVER #https://github.com/go-ole/go-ole/blob/7dfdcf409020452e29b4babcbb22f984d2aa308a/constants.go#L11

try:
    i = 0
    while i < 100000:
        i += 1
        if (i % 1000 == 0):
            print "%7d %.1fMB" % (i,GetMemoryUsageMB())
        comtypes.CoInitializeEx(comtypes.COINIT_MULTITHREADED) #https://github.com/enthought/comtypes/blob/d3fbdd0c2933c9671e80d7407a0320925abc8bc5/comtypes/__init__.py#L156
        #com_object = comtypes.client.CreateObject(progid) #https://github.com/enthought/comtypes/blob/d3fbdd0c2933c9671e80d7407a0320925abc8bc5/comtypes/client/__init__.py#L205
        com_object = comtypes.CoCreateInstance(clsid, clsctx=clsctx, interface=None) # https://github.com/enthought/comtypes/blob/d3fbdd0c2933c9671e80d7407a0320925abc8bc5/comtypes/__init__.py#L1215
        iface = com_object.QueryInterface(comtypes.automation.IDispatch)
        #iface.Invoke()   #https://github.com/enthought/comtypes/blob/d3fbdd0c2933c9671e80d7407a0320925abc8bc5/comtypes/automation.py#L732
        del iface           #calls release https://github.com/enthought/comtypes/blob/d3fbdd0c2933c9671e80d7407a0320925abc8bc5/comtypes/__init__.py#L905
        del com_object
        comtypes.CoUninitialize()
        
except Exception, e:
    print 'Exception: '+ str(e)
    print traceback.format_exc()

'''
for key in dir(iface):
    method = getattr(iface,key)
    if str(type(method)) == "<type 'instance'>":
        print key
        for sub_method in dir(method):
            if not sub_method.startswith("_") and not "clsid" in sub_method.lower():
                print "\t"+sub_method
    else:
        print "\t",key,'=',method
'''

print "End %.2fMB" % GetMemoryUsageMB()

#comtypes calls CoUninitialize at shutdown https://github.com/enthought/comtypes/blob/d3fbdd0c2933c9671e80d7407a0320925abc8bc5/comtypes/__init__.py#L175
#comtypes.CoUninitialize()

Output on a Windows 10 system:

python testwmi.py
Start 10.92MB  
   1000 11.5MB 
   2000 11.6MB 
   3000 11.6MB 
   4000 11.6MB 
   5000 11.6MB 
 ... omitted ...
  98000 11.8MB 
  99000 11.8MB 
 100000 11.8MB 
End 11.83MB