path: root/glances/plugins/cpu/model.py

# -*- coding: utf-8 -*-
#
# This file is part of Glances.
#
# SPDX-FileCopyrightText: 2022 Nicolas Hennion <nicolas@nicolargo.com>
#
# SPDX-License-Identifier: LGPL-3.0-only
#

"""CPU plugin."""

from glances.timer import getTimeSinceLastUpdate
from glances.globals import LINUX, WINDOWS, SUNOS, iterkeys
from glances.cpu_percent import cpu_percent
from glances.plugins.core.model import PluginModel as CorePluginModel
from glances.plugins.plugin.model import GlancesPluginModel

import psutil

# Fields description
# description: human readable description
# short_name: shortname to use un UI
# unit: unit type
# rate: is it a rate ? If yes, // by time_since_update when displayed,
# min_symbol: Auto unit should be used if value > than 1 'X' (K, M, G)...
fields_description = {
    'total': {
        'getter': 'compute',
        'description': 'Sum of all CPU percentages (except idle).',
        'unit': 'percent'
    },
    'system': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': 'percent time spent in kernel space. System CPU time is the \
time spent running code in the Operating System kernel.',
        'unit': 'percent',
    },
    'user': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': 'CPU percent time spent in user space. \
User CPU time is the time spent on the processor running your program\'s code (or code in libraries).',
        'unit': 'percent',
    },
    'iowait': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': '*(Linux)*: percent time spent by the CPU waiting for I/O \
operations to complete.',
        'unit': 'percent',
    },
    'dpc': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': '*(Windows)*: time spent servicing deferred procedure calls (DPCs)',
        'unit': 'percent',
    },
    'idle': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': 'percent of CPU used by any program. Every program or task \
that runs on a computer system occupies a certain amount of processing \
time on the CPU. If the CPU has completed all tasks it is idle.',
        'unit': 'percent',
    },
    'irq': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': '*(Linux and BSD)*: percent time spent servicing/handling \
hardware/software interrupts. Time servicing interrupts (hardware + \
software).',
        'unit': 'percent',
    },
    'nice': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': '*(Unix)*: percent time occupied by user level processes with \
a positive nice value. The time the CPU has spent running users\' \
processes that have been *niced*.',
        'unit': 'percent',
    },
    'steal': {
        'getter': {'fct': 'psutil.cpu_times_percent', 'arg': {'interval': 0.0}},
        'description': '*(Linux)*: percentage of time a virtual CPU waits for a real \
CPU while the hypervisor is servicing another virtual processor.',
        'unit': 'percent',
    },
    'ctx_switches': {
        'getter': {'fct': 'psutil.cpu_stats', 'arg': {}},
        'description': 'number of context switches (voluntary + involuntary) per \
second. A context switch is a procedure that a computer\'s CPU (central \
processing unit) follows to change from one task (or process) to \
another while ensuring that the tasks do not conflict.',
        'unit': 'number',
        'rate': True,
        'min_symbol': 'K',
        'short_name': 'ctx_sw',
    },
    'interrupts': {
        'getter': {'fct': 'psutil.cpu_stats', 'arg': {}},
        'description': 'number of interrupts per second.',
        'unit': 'number',
        'rate': True,
        'min_symbol': 'K',
        'short_name': 'inter',
    },
    'soft_interrupts': {
        'getter': {'fct': 'psutil.cpu_stats', 'arg': {}},
        'description': 'number of software interrupts per second. Always set to \
0 on Windows and SunOS.',
        'unit': 'number',
        'rate': True,
        'min_symbol': 'K',
        'short_name': 'sw_int',
    },
    'syscalls': {
        'getter': {'fct': 'psutil.cpu_stats', 'arg': {}},
        'description': 'number of system calls per second. Always 0 on Linux OS.',
        'unit': 'number',
        'rate': True,
        'min_symbol': 'K',
        'short_name': 'sys_call',
    },
    'cpucore': {
        'getter': 'compute',
        'description': 'Total number of CPU core.',
        'unit': 'number'
    },
    'time_since_update': {
        'getter': 'compute',
        'description': 'Number of seconds since last update.',
        'unit': 'seconds'
    },
}

# SNMP OID
# percentage of user CPU time: .1.3.6.1.4.1.2021.11.9.0
# percentages of system CPU time: .1.3.6.1.4.1.2021.11.10.0
# percentages of idle CPU time: .1.3.6.1.4.1.2021.11.11.0
snmp_oid = {
    'default': {
        'user': '1.3.6.1.4.1.2021.11.9.0',
        'system': '1.3.6.1.4.1.2021.11.10.0',
        'idle': '1.3.6.1.4.1.2021.11.11.0',
    },
    'windows': {'percent': '1.3.6.1.2.1.25.3.3.1.2'},
    'esxi': {'percent': '1.3.6.1.2.1.25.3.3.1.2'},
    'netapp': {
        'system': '1.3.6.1.4.1.789.1.2.1.3.0',
        'idle': '1.3.6.1.4.1.789.1.2.1.5.0',
        'cpucore': '1.3.6.1.4.1.789.1.2.1.6.0',
    },
}

# Define the history items list
# - 'name' define the stat identifier
# - 'y_unit' define the Y label
items_history_list = [
    {'name': 'user', 'description': 'User CPU usage', 'y_unit': '%'},
    {'name': 'system', 'description': 'System CPU usage', 'y_unit': '%'},
]


class PluginModel(GlancesPluginModel):
    """Glances CPU plugin.

    'stats' is a dictionary that contains the system-wide CPU utilization as a
    percentage.
    """

    def __init__(self, args=None, config=None):
        """Init the CPU plugin."""
        super(PluginModel, self).__init__(
            args=args, config=config, items_history_list=items_history_list, fields_description=fields_description
        )

        # We want to display the stat in the curse interface
        self.display_curse = True

        # Call CorePluginModel in order to display the core number
        try:
            self.nb_log_core = CorePluginModel(args=self.args).update()["log"]
        except Exception:
            self.nb_log_core = 1

    def cpucore(self, stats):
        """Core number is needed to compute the CTX switch limit"""
        return self.nb_log_core

    def total(self, stats):
        """Return the sum of all CPU percentages (except idle)
        Use a function shared with percpu plugin"""
        return cpu_percent.get()

    @GlancesPluginModel._check_decorator
    @GlancesPluginModel._log_result_decorator
    def update(self):
        """Update CPU stats using the input method."""
        # Grab stats into self.stats
        if self.input_method == 'local':
            stats = self.update_cpu_local()
        elif self.input_method == 'snmp':
            stats = self.update_cpu_snmp()
        else:
            stats = self.get_init_value()

        # Update the stats
        self.stats = stats

        return self.stats

    def update_cpu_local(self):
        """Update CPU stats using psutil."""

        # Init new stats
        stats = self.get_init_value()

        # Grab CPU stats using psutil's cpu_percent and cpu_times_percent
        # Get all possible values for CPU stats: user, system, idle,
        # nice (UNIX), iowait (Linux), irq (Linux, FreeBSD), steal (Linux 2.6.11+)
        # The following stats are returned by the API but not displayed in the UI:
        # softirq (Linux), guest (Linux 2.6.24+), guest_nice (Linux 3.2.0+)
        #
        # Standards stats
        # - user: time spent by normal processes executing in user mode; on Linux this also includes guest time
        # - system: time spent by processes executing in kernel mode
        # - idle: time spent doing nothing
        # - nice (UNIX): time spent by niced (prioritized) processes executing in user mode
        #                on Linux this also includes guest_nice time
        # - iowait (Linux): time spent waiting for I/O to complete.
        #                   This is not accounted in idle time counter.
        # - irq (Linux, BSD): time spent for servicing hardware interrupts
        # - softirq (Linux): time spent for servicing software interrupts
        # - steal (Linux 2.6.11+): time spent by other operating systems running in a virtualized environment
        # - guest (Linux 2.6.24+): time spent running a virtual CPU for guest operating systems under
        #                          the control of the Linux kernel
        # - guest_nice (Linux 3.2.0+): time spent running a niced guest (virtual CPU for guest operating systems
        #                              under the control of the Linux kernel)
        # - interrupt (Windows): time spent for servicing hardware interrupts ( similar to “irq” on UNIX)
        # - dpc (Windows): time spent servicing deferred procedure calls (DPCs)
        #
        # Additional CPU stats (number of events not as a %; psutil>=4.1.0)
        # - ctx_switches: number of context switches (voluntary + involuntary) since boot.
        # - interrupts: number of interrupts since boot.
        # - soft_interrupts: number of software interrupts since boot. Always set to 0 on Windows and SunOS.
        # - syscalls: number of system calls since boot. Always set to 0 on Linux.
        self.update_local(stats)

        return stats

    def update_cpu_snmp(self):
        """Update CPU stats using SNMP."""

        # Init new stats
        stats = self.get_init_value()

        # Update stats using SNMP
        if self.short_system_name in ('windows', 'esxi'):
            # Windows or VMWare ESXi
            # You can find the CPU utilization of windows system by querying the oid
            # Give also the number of core (number of element in the table)
            try:
                cpu_stats = self.get_stats_snmp(snmp_oid=snmp_oid[self.short_system_name], bulk=True)
            except KeyError:
                self.reset()

            # Iter through CPU and compute the idle CPU stats
            stats['nb_log_core'] = 0
            stats['idle'] = 0
            for c in cpu_stats:
                if c.startswith('percent'):
                    stats['idle'] += float(cpu_stats['percent.3'])
                    stats['nb_log_core'] += 1
            if stats['nb_log_core'] > 0:
                stats['idle'] = stats['idle'] / stats['nb_log_core']
            stats['idle'] = 100 - stats['idle']
            stats['total'] = 100 - stats['idle']

        else:
            # Default behavior
            try:
                stats = self.get_stats_snmp(snmp_oid=snmp_oid[self.short_system_name])
            except KeyError:
                stats = self.get_stats_snmp(snmp_oid=snmp_oid['default'])

            if stats['idle'] == '':
                self.reset()
                return self.stats

            # Convert SNMP stats to float
            for key in iterkeys(stats):
                stats[key] = float(stats[key])
            stats['total'] = 100 - stats['idle']

        return stats

    def update_views(self):
        """Update stats views."""
        # Call the father's method
        super(PluginModel, self).update_views()

        # Add specifics information
        # Alert and log
        for key in ['user', 'system', 'iowait', 'dpc', 'total']:
            if key in self.stats:
                self.views[key]['decoration'] = self.get_alert_log(self.stats[key], header=key)
        # Alert only
        for key in ['steal']:
            if key in self.stats:
                self.views[key]['decoration'] = self.get_alert(self.stats[key],