"""Utilities for the win32 Performance Data Helper module
Example:
To get a single bit of data:
>>> import win32pdhutil
>>> win32pdhutil.GetPerformanceAttributes("Memory", "Available Bytes")
6053888
>>> win32pdhutil.FindPerformanceAttributesByName("python", counter="Virtual Bytes")
[22278144]
First example returns data which is not associated with any specific instance.
The second example reads data for a specific instance - hence the list return -
it would return one result for each instance of Python running.
In general, it can be tricky finding exactly the "name" of the data you wish to query.
Although you can use <om win32pdh.EnumObjectItems>(None,None,(eg)"Memory", -1) to do this,
the easiest way is often to simply use PerfMon to find out the names.
"""
import win32pdh, time
error = win32pdh.error
# Handle some localization issues.
# see http://support.microsoft.com/default.aspx?scid=http://support.microsoft.com:80/support/kb/articles/Q287/1/59.asp&NoWebContent=1
# Build a map of english_counter_name: counter_id
counter_english_map = {}
def find_pdh_counter_localized_name(english_name, machine_name = None):
if not counter_english_map:
import win32api, win32con
counter_reg_value = win32api.RegQueryValueEx(win32con.HKEY_PERFORMANCE_DATA,
"Counter 009")
counter_list = counter_reg_value[0]
for i in xrange(0, len(counter_list) - 1, 2):
try:
counter_id = int(counter_list[i])
except ValueError:
continue
counter_english_map[counter_list[i+1].lower()] = counter_id
return win32pdh.LookupPerfNameByIndex(machine_name, counter_english_map[english_name.lower()])
def GetPerformanceAttributes(object, counter, instance = None, inum=-1,
format = win32pdh.PDH_FMT_LONG, machine=None):
# NOTE: Many counters require 2 samples to give accurate results,
# including "% Processor Time" (as by definition, at any instant, a
# thread's CPU usage is either 0 or 100). To read counters like this,
# you should copy this function, but keep the counter open, and call
# CollectQueryData() each time you need to know.
# See http://support.microsoft.com/default.aspx?scid=kb;EN-US;q262938
# and http://msdn.microsoft.com/library/en-us/dnperfmo/html/perfmonpt2.asp
# My older explanation for this was that the "AddCounter" process forced
# the CPU to 100%, but the above makes more sense :)
path = win32pdh.MakeCounterPath( (machine,object,instance, None, inum,counter) )
hq = win32pdh.OpenQuery()
try:
hc = win32pdh.AddCounter(hq, path)
try:
win32pdh.CollectQueryData(hq)
type, val = win32pdh.GetFormattedCounterValue(hc, format)
return val
finally:
win32pdh.RemoveCounter(hc)
finally:
win32pdh.CloseQuery(hq)
def FindPerformanceAttributesByName(instanceName, object = None,
counter = None,
format = win32pdh.PDH_FMT_LONG,
machine = None, bRefresh=0):
"""Find peformance attributes by (case insensitive) instance name.
Given a process name, return a list with the requested attributes.
Most useful for returning a tuple of PIDs given a process name.
"""
if object is None: object = find_pdh_counter_localized_name("Process", machine)
if counter is None: counter = find_pdh_counter_localized_name("ID Process", machine)
if bRefresh: # PDH docs say this is how you do a refresh.
win32pdh.EnumObjects(None, machine, 0, 1)
instanceName = instanceName.lower()
items, instances = win32pdh.EnumObjectItems(None,None,object, -1)
# Track multiple instances.
instance_dict = {}
for instance in instances:
try:
instance_dict[instance] = instance_dict[instance] + 1
except KeyError:
instance_dict[instance] = 0
ret = []
for instance, max_instances in instance_dict.iteritems():
for inum in xrange(max_instances+1):
if instance.lower() == instanceName:
ret.append(GetPerformanceAttributes(object, counter,
instance, inum, format,
machine))
return ret
def ShowAllProcesses():
object = find_pdh_counter_localized_name("Process")
items, instances = win32pdh.EnumObjectItems(None,None,object,
win32pdh.PERF_DETAIL_WIZARD)
# Need to track multiple instances of the same name.
instance_dict = {}
for instance in instances:
try:
instance_dict[instance] = instance_dict[instance] + 1
except KeyError:
instance_dict[instance] = 0
# Bit of a hack to get useful info.
items = [find_pdh_counter_localized_name("ID Process")] + items[:5]
print "Process Name", ",".join(items)
for instance, max_instances in instance_dict.iteritems():
for inum in xrange(max_instances+1):
hq = win32pdh.OpenQuery()
hcs = []
for item in items:
path = win32pdh.MakeCounterPath( (None,object,instance,
None, inum, item) )
hcs.append(win32pdh.AddCounter(hq, path))
win32pdh.CollectQueryData(hq)
# as per http://support.microsoft.com/default.aspx?scid=kb;EN-US;q262938, some "%" based
# counters need two collections
time.sleep(0.01)
win32pdh.CollectQueryData(hq)
print "%-15s\t" % (instance[:15]),
for hc in hcs:
type, val = win32pdh.GetFormattedCounterValue(hc, win32pdh.PDH_FMT_LONG)
print "%5d" % (val),
win32pdh.RemoveCounter(hc)
print
win32pdh.CloseQuery(hq)
# NOTE: This BrowseCallback doesn't seem to work on Vista for markh.
# XXX - look at why!?
def BrowseCallBackDemo(counter):
machine, object, instance, parentInstance, index, counterName = \
win32pdh.ParseCounterPath(counter)
result = GetPerformanceAttributes(object, counterName, instance, index,
win32pdh.PDH_FMT_DOUBLE, machine)
print "Value of '%s' is" % counter, result
print "Added '%s' on object '%s' (machine %s), instance %s(%d)-parent of %s" \
% (counterName, object, machine, instance, index, parentInstance)
def browse(callback = BrowseCallBackDemo, title="Python Browser",
level=win32pdh.PERF_DETAIL_WIZARD):
win32pdh.BrowseCounters(None,0, callback, level, title)
if __name__=='__main__':
ShowAllProcesses()
# Show how to get a couple of attributes by name.
counter = find_pdh_counter_localized_name("Virtual Bytes")
print "Virtual Bytes = ", FindPerformanceAttributesByName("python",
counter=counter)
print "Available Bytes = ", GetPerformanceAttributes(
find_pdh_counter_localized_name("Memory"),
find_pdh_counter_localized_name("Available Bytes"))
# And a browser.
print "Browsing for counters..."
browse()
|