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-rw-r--r--python.d/cpuidle.chart.py143
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diff --git a/python.d/cpuidle.chart.py b/python.d/cpuidle.chart.py
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+# -*- coding: utf-8 -*-
+# Description: cpuidle netdata python.d module
+# Author: Steven Noonan (tycho)
+
+import glob
+import os
+import platform
+import time
+from base import SimpleService
+
+import ctypes
+syscall = ctypes.CDLL('libc.so.6').syscall
+
+# default module values (can be overridden per job in `config`)
+# update_every = 2
+
+class Service(SimpleService):
+ def __init__(self, configuration=None, name=None):
+ prefix = os.getenv('NETDATA_HOST_PREFIX', "")
+ if prefix.endswith('/'):
+ prefix = prefix[:-1]
+ self.sys_dir = prefix + "/sys/devices/system/cpu"
+ self.schedstat_path = prefix + "/proc/schedstat"
+ SimpleService.__init__(self, configuration=configuration, name=name)
+ self.order = []
+ self.definitions = {}
+ self._orig_name = ""
+ self.assignment = {}
+
+ def __gettid(self):
+ # This is horrendous. We need the *thread id* (not the *process id*),
+ # but there's no Python standard library way of doing that. If you need
+ # to enable this module on a non-x86 machine type, you'll have to find
+ # the Linux syscall number for gettid() and add it to the dictionary
+ # below.
+ syscalls = {
+ 'i386': 224,
+ 'x86_64': 186,
+ }
+ if platform.machine() not in syscalls:
+ return None
+ tid = syscall(syscalls[platform.machine()])
+ return tid
+
+ def __wake_cpus(self):
+ # Requires Python 3.3+. This will "tickle" each CPU to force it to
+ # update its idle counters.
+ if hasattr(os, 'sched_setaffinity'):
+ pid = self.__gettid()
+ save_affinity = os.sched_getaffinity(pid)
+ for idx in range(0, len(self.assignment)):
+ os.sched_setaffinity(pid, [idx])
+ os.sched_getaffinity(pid)
+ os.sched_setaffinity(pid, save_affinity)
+
+ def __read_schedstat(self):
+ cpus = {}
+ for line in open(self.schedstat_path, 'r'):
+ if not line.startswith('cpu'):
+ continue
+ line = line.rstrip().split()
+ cpu = line[0]
+ active_time = line[7]
+ cpus[cpu] = int(active_time) // 1000
+ return cpus
+
+ def _get_data(self):
+ results = {}
+
+ # This line is critical for the stats to update. If we don't "tickle"
+ # all the CPUs, then all the counters stop counting.
+ self.__wake_cpus()
+
+ # Use the kernel scheduler stats to determine how much time was spent
+ # in C0 (active).
+ schedstat = self.__read_schedstat()
+
+ for cpu, metrics in self.assignment.items():
+ update_time = schedstat[cpu]
+ results[cpu + '_active_time'] = update_time
+
+ for metric, path in metrics.items():
+ residency = int(open(path, 'r').read())
+ results[metric] = residency
+
+ return results
+
+ def check(self):
+ if self.__gettid() is None:
+ self.error("Cannot get thread ID. Stats would be completely broken.")
+ return False
+
+ self._orig_name = self.chart_name
+
+ for path in sorted(glob.glob(self.sys_dir + '/cpu*/cpuidle/state*/name')):
+ # ['', 'sys', 'devices', 'system', 'cpu', 'cpu0', 'cpuidle', 'state3', 'name']
+ path_elem = path.split('/')
+ cpu = path_elem[-4]
+ state = path_elem[-2]
+ statename = open(path, 'rt').read().rstrip()
+
+ orderid = '%s_cpuidle' % (cpu,)
+ if orderid not in self.definitions:
+ self.order.append(orderid)
+ active_name = '%s_active_time' % (cpu,)
+ self.definitions[orderid] = {
+ 'options': [None, 'C-state residency', 'time%', 'cpuidle', None, 'stacked'],
+ 'lines': [
+ [active_name, 'C0 (active)', 'percentage-of-incremental-row', 1, 1],
+ ],
+ }
+ self.assignment[cpu] = {}
+
+ defid = '%s_%s_time' % (orderid, state)
+
+ self.definitions[orderid]['lines'].append(
+ [defid, statename, 'percentage-of-incremental-row', 1, 1]
+ )
+
+ self.assignment[cpu][defid] = '/'.join(path_elem[:-1] + ['time'])
+
+ # Sort order by kernel-specified CPU index
+ self.order.sort(key=lambda x: int(x.split('_')[0][3:]))
+
+ if len(self.definitions) == 0:
+ self.error("couldn't find cstate stats")
+ return False
+
+ return True
+
+ def create(self):
+ self.chart_name = "cpu"
+ status = SimpleService.create(self)
+ self.chart_name = self._orig_name
+ return status
+
+ def update(self, interval):
+ self.chart_name = "cpu"
+ status = SimpleService.update(self, interval=interval)
+ self.chart_name = self._orig_name
+ return status
+
+# vim: set ts=4 sts=4 sw=4 et: