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.. module:: psutil
   :synopsis: psutil module
.. moduleauthor:: Giampaolo Rodola' <grodola@gmail.com>

psutil documentation

Quick links

About

psutil (python system and process utilities) is a cross-platform library for retrieving information on running processes and system utilization (CPU, memory, disks, network, sensors) in Python. It is useful mainly for system monitoring, profiling, limiting process resources and the management of running processes. It implements many functionalities offered by UNIX command line tools such as: ps, top, lsof, netstat, ifconfig, who, df, kill, free, nice, ionice, iostat, iotop, uptime, pidof, tty, taskset, pmap. psutil currently supports the following platforms:

  • Linux
  • Windows
  • OSX,
  • FreeBSD, OpenBSD, NetBSD
  • Sun Solaris
  • AIX

...both 32-bit and 64-bit architectures, with Python versions from 2.6 to 3.6 (users of Python 2.4 and 2.5 may use 2.1.3 version). PyPy is also known to work.

The psutil documentation you're reading is distributed as a single HTML page.

Install

The easiest way to install psutil is via pip:

pip install psutil

On UNIX this requires a C compiler (e.g. gcc) installed. On Windows pip will automatically retrieve a pre-compiled wheel version from PYPI repository. Alternatively, see more detailed install instructions.

System related functions

CPU

.. function:: cpu_times(percpu=False)

  Return system CPU times as a named tuple.
  Every attribute represents the seconds the CPU has spent in the given mode.
  The attributes availability varies depending on the platform:

  - **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

  Platform-specific fields:

  - **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
  - **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);
    DPCs are interrupts that run at a lower priority than standard interrupts.

  When *percpu* is ``True`` return a list of named tuples for each logical CPU
  on the system.
  First element of the list refers to first CPU, second element to second CPU
  and so on.
  The order of the list is consistent across calls.
  Example output on Linux:

    >>> import psutil
    >>> psutil.cpu_times()
    scputimes(user=17411.7, nice=77.99, system=3797.02, idle=51266.57, iowait=732.58, irq=0.01, softirq=142.43, steal=0.0, guest=0.0, guest_nice=0.0)

  .. versionchanged:: 4.1.0 added *interrupt* and *dpc* fields on Windows.

.. function:: cpu_percent(interval=None, percpu=False)

  Return a float representing the current system-wide CPU utilization as a
  percentage. When *interval* is > ``0.0`` compares system CPU times elapsed
  before and after the interval (blocking).
  When *interval* is ``0.0`` or ``None`` compares system CPU times elapsed
  since last call or module import, returning immediately.
  That means the first time this is called it will return a meaningless ``0.0``
  value which you are supposed to ignore.
  In this case it is recommended for accuracy that this function be called with
  at least ``0.1`` seconds between calls.
  When *percpu* is ``True`` returns a list of floats representing the
  utilization as a percentage for each CPU.
  First element of the list refers to first CPU, second element to second CPU
  and so on. The order of the list is consistent across calls.

    >>> import psutil
    >>> # blocking
    >>> psutil.cpu_percent(interval=1)
    2.0
    >>> # non-blocking (percentage since last call)
    >>> psutil.cpu_percent(interval=None)
    2.9
    >>> # blocking, per-cpu
    >>> psutil.cpu_percent(interval=1, percpu=True)
    [2.0, 1.0]
    >>>

  .. warning::
    the first time this function is called with *interval* = ``0.0`` or ``None``
    it will return a meaningless ``0.0`` value which you are supposed to
    ignore.

.. function:: cpu_times_percent(interval=None, percpu=False)

  Same as :func:`cpu_percent()` but provides utilization percentages for each
  specific CPU time as is returned by
  :func:`psutil.cpu_times(percpu=True)<cpu_times()>`.
  *interval* and
  *percpu* arguments have the same meaning as in :func:`cpu_percent()`.
  On Linux "guest" and "guest_nice" percentages are not accounted in "user"
  and "user_nice" percentages.

  .. warning::
    the first time this function is called with *interval* = ``0.0`` or
    ``None`` it will return a meaningless ``0.0`` value which you are supposed
    to ignore.

  .. versionchanged::
    4.1.0 two new *interrupt* and *dpc* fields are returned on Windows.

.. function:: cpu_count(logical=True)

  Return the number of logical CPUs in the system (same as
  `os.cpu_count() <http://docs.python.org/3/library/os.html#os.cpu_count>`__
  in Python 3.4) or ``None`` if undetermined.
  This number may not be equivalent to the number of CPUs the current process
  can actually use in case process CPU affinity has been changed or Linux
  cgroups are being used.
  The number of usable CPUs can be obtained with
  ``len(psutil.Process().cpu_affinity())``.
  If *logical* is ``False`` return the number of physical cores only (hyper
  thread CPUs are excluded).
  On OpenBSD and NetBSD ``psutil.cpu_count(logical=False)`` always return
  ``None``. Example on a system having 2 physical hyper-thread CPU cores:

    >>> import psutil
    >>> psutil.cpu_count()
    4
    >>> psutil.cpu_count(logical=False)
    2

  Example returning the number of CPUs usable by the current process:

    >>> len(psutil.Process().cpu_affinity())
    1

.. function:: cpu_stats()

  Return various CPU statistics as a named tuple:

  - **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.

  Example (Linux):

  .. code-block:: python

     >>> import psutil
     >>> psutil.cpu_stats()
     scpustats(ctx_switches=20455687, interrupts=6598984, soft_interrupts=2134212, syscalls=0)

  .. versionadded:: 4.1.0


.. function:: cpu_freq(percpu=False)

    Return CPU frequency as a nameduple including *current*, *min* and *max*
    frequencies expressed in Mhz.
    On Linux *current* frequency reports the real-time value, on all other
    platforms it represents the nominal "fixed" value.
    If *percpu* is ``True`` and the system supports per-cpu frequency
    retrieval (Linux only) a list of frequencies is returned for each CPU,
    if not, a list with a single element is returned.
    If *min* and *max* cannot be determined they are set to ``0``.

    Example (Linux):

    .. code-block:: python

       >>> import psutil
       >>> psutil.cpu_freq()
       scpufreq(current=931.42925, min=800.0, max=3500.0)
       >>> psutil.cpu_freq(percpu=True)
       [scpufreq(current=2394.945, min=800.0, max=3500.0),
        scpufreq(current=2236.812, min=800.0, max=3500.0),
        scpufreq(current=1703.609, min=800.0, max=3500.0),
        scpufreq(current=1754.289, min=800.0, max=3500.0)]

    Availability: Linux, OSX, Windows

    .. versionadded:: 5.1.0


Memory

.. function:: virtual_memory()

  Return statistics about system memory usage as a named tuple including the
  following fields, expressed in bytes. Main metrics:

  - **total**: total physical memory.
  - **available**: the memory that can be given instantly to processes without
    the system going into swap.
    This is calculated by summing different memory values depending on the
    platform and it is supposed to be used to monitor actual memory usage in a
    cross platform fashion.

  Other metrics:

  - **used**: memory used, calculated differently depending on the platform and
    designed for informational purposes only. **total - free** does not
    necessarily match **used**.
  - **free**: memory not being used at all (zeroed) that is readily available;
    note that this doesn't reflect the actual memory available (use
    **available** instead). **total - used** does not necessarily match
    **free**.
  - **active** *(UNIX)*: memory currently in use or very recently used, and so
    it is in RAM.
  - **inactive** *(UNIX)*: memory that is marked as not used.
  - **buffers** *(Linux, BSD)*: cache for things like file system metadata.
  - **cached** *(Linux, BSD)*: cache for various things.
  - **shared** *(Linux, BSD)*: memory that may be simultaneously accessed by
    multiple processes.
  - **wired** *(BSD, OSX)*: memory that is marked to always stay in RAM. It is
    never moved to disk.

  The sum of **used** and **available** does not necessarily equal **total**.
  On Windows **available** and **free** are the same.
  See `meminfo.py <https://github.com/giampaolo/psutil/blob/master/scripts/meminfo.py>`__
  script providing an example on how to convert bytes in a human readable form.

  .. note:: if you just want to know how much physical memory is left in a
    cross platform fashion simply rely on the **available** field.

  >>> import psutil
  >>> mem = psutil.virtual_memory()
  >>> mem
  svmem(total=10367352832, available=6472179712, percent=37.6, used=8186245120, free=2181107712, active=4748992512, inactive=2758115328, buffers=790724608, cached=3500347392, shared=787554304)
  >>>
  >>> THRESHOLD = 100 * 1024 * 1024  # 100MB
  >>> if mem.available <= THRESHOLD:
  ...     print("warning")
  ...
  >>>

  .. versionchanged:: 4.2.0 added *shared* metrics on Linux.

  .. versionchanged:: 4.4.0 *available* and *used* values on Linux are more
    precise and match "free" cmdline utility.


.. function:: swap_memory()

  Return system swap memory statistics as a named tuple including the following
  fields:

  * **total**: total swap memory in bytes
  * **used**: used swap memory in bytes
  * **free**: free swap memory in bytes
  * **percent**: the percentage usage calculated as ``(total - available) / total * 100``
  * **sin**: the number of bytes the system has swapped in from disk
    (cumulative)
  * **sout**: the number of bytes the system has swapped out from disk
    (cumulative)

  **sin** and **sout** on Windows are always set to ``0``.
  See `meminfo.py <https://github.com/giampaolo/psutil/blob/master/scripts/meminfo.py>`__
  script providing an example on how to convert bytes in a human readable form.

    >>> import psutil
    >>> psutil.swap_memory()
    sswap(total=2097147904L, used=886620160L, free=1210527744L, percent=42.3, sin=1050411008, sout=1906720768)

  .. versionchanged:: 5.2.3 on Linux this function relies on /proc fs instead
     of sysinfo() syscall so that it can be used in conjunction with
     :const:`psutil.PROCFS_PATH` in order to retrieve memory info about
     Linux containers such as Docker and Heroku.

Disks

.. function:: disk_partitions(all=False)

  Return all mounted disk partitions as a list of named tuples including device,
  mount point and filesystem type, similarly to "df" command on UNIX. If *all*
  parameter is ``False`` it tries to distinguish and return physical devices
  only (e.g. hard disks, cd-rom drives, USB keys) and ignore all others
  (e.g. memory partitions such as
  `/dev/shm <http://www.cyberciti.biz/tips/what-is-devshm-and-its-practical-usage.html>`__).
  Note that this may not be fully reliable on all systems (e.g. on BSD this
  parameter is ignored).
  Named tuple's **fstype** field is a string which varies depending on the
  platform.
  On Linux it can be one of the values found in /proc/filesystems (e.g.
  ``'ext3'`` for an ext3 hard drive o ``'iso9660'`` for the CD-ROM drive).
  On Windows it is determined via
  `GetDriveType <http://msdn.microsoft.com/en-us/library/aa364939(v=vs.85).aspx>`__
  and can be either ``"removable"``, ``"fixed"``, ``"remote"``, ``"cdrom"``,
  ``"unmounted"`` or ``"ramdisk"``. On OSX and BSD it is retrieved via
  `getfsstat(2) <http://www.manpagez.com/man/2/getfsstat/>`__. See
  `disk_usage.py <https://github.com/giampaolo/psutil/blob/master/scripts/disk_usage.py>`__
  script providing an example usage.

    >>> import psutil
    >>> psutil.disk_partitions()
    [sdiskpart(device='/dev/sda3', mountpoint='/', fstype='ext4', opts='rw,errors=remount-ro'),
     sdiskpart(device='/dev/sda7', mountpoint='/home', fstype='ext4', opts='rw')]

.. function:: disk_usage(path)

  Return disk usage statistics about the partition which contains the given
  *path* as a named tuple including **total**, **used** and **free** space
  expressed in bytes, plus the **percentage** usage.
  `OSError <http://docs.python.org/3/library/exceptions.html#OSError>`__ is
  raised if *path* does not exist.
  Starting from `Python 3.3 <http://bugs.python.org/issue12442>`__  this is
  also available as
  `shutil.disk_usage() <http://docs.python.org/3/library/shutil.html#shutil.disk_usage>`__.
  See `disk_usage.py <https://github.com/giampaolo/psutil/blob/master/scripts/disk_usage.py>`__ script providing an example usage.

    >>> import psutil
    >>> psutil.disk_usage('/')
    sdiskusage(total=21378641920, used=4809781248, free=15482871808, percent=22.5)

  .. note::
    UNIX usually reserves 5% of the total disk space for the root user.
    *total* and *used* fields on UNIX refer to the overall total and used
    space, whereas *free* represents the space available for the **user** and
    *percent* represents the **user** utilization (see
    `source code <https://github.com/giampaolo/psutil/blob/3dea30d583b8c1275057edb1b3b720813b4d0f60/psutil/_psposix.py#L123>`__).
    That is why *percent* value may look 5% bigger than what you would expect
    it to be.
    Also note that both 4 values match "df" cmdline utility.

  .. versionchanged::
    4.3.0 *percent* value takes root reserved space into account.

.. function:: disk_io_counters(perdisk=False, nowrap=True)

  Return system-wide disk I/O statistics as a named tuple including the
  following fields:

  - **read_count**: number of reads
  - **write_count**: number of writes
  - **read_bytes**: number of bytes read
  - **write_bytes**: number of bytes written

  Platform-specific fields:

  - **read_time**: (all except *NetBSD* and *OpenBSD*) time spent reading from
    disk (in milliseconds)
  - **write_time**: (all except *NetBSD* and *OpenBSD*) time spent writing to disk
    (in milliseconds)
  - **busy_time**: (*Linux*, *FreeBSD*) time spent doing actual I/Os (in
    milliseconds)
  - **read_merged_count** (*Linux*): number of merged reads
    (see `iostat doc <https://www.kernel.org/doc/Documentation/iostats.txt>`__)
  - **write_merged_count** (*Linux*): number of merged writes
    (see `iostats doc <https://www.kernel.org/doc/Documentation/iostats.txt>`__)

  If *perdisk* is ``True`` return the same information for every physical disk
  installed on the system as a dictionary with partition names as the keys and
  the named tuple described above as the values.
  See `iotop.py <https://github.com/giampaolo/psutil/blob/master/scripts/iotop.py>`__
  for an example application.
  On some systems such as Linux, on a very busy or long-lived system, the
  numbers returned by the kernel may overflow and wrap (restart from zero).
  If *nowrap* is ``True`` psutil will detect and adjust those numbers across
  function calls and add "old value" to "new value" so that the returned
  numbers will always be increasing or remain the same, but never decrease.
  ``disk_io_counters.cache_clear()`` can be used to invalidate the *nowrap*
  cache.

    >>> import psutil
    >>> psutil.disk_io_counters()
    sdiskio(read_count=8141, write_count=2431, read_bytes=290203, write_bytes=537676, read_time=5868, write_time=94922)
    >>>
    >>> psutil.disk_io_counters(perdisk=True)
    {'sda1': sdiskio(read_count=920, write_count=1, read_bytes=2933248, write_bytes=512, read_time=6016, write_time=4),
     'sda2': sdiskio(read_count=18707, write_count=8830, read_bytes=6060, write_bytes=3443, read_time=24585, write_time=1572),
     'sdb1': sdiskio(read_count=161, write_count=0, read_bytes=786432, write_bytes=0, read_time=44, write_time=0)}

  .. note::
    on Windows ``"diskperf -y"`` command may need to be executed first
    otherwise this function won't find any disk.

  .. versionchanged::
    5.3.0 numbers no longer wrap (restart from zero) across calls thanks to new
    *nowrap* argument.

  .. versionchanged::
    4.0.0 added *busy_time* (Linux, FreeBSD), *read_merged_count* and
    *write_merged_count* (Linux) fields.

  .. versionchanged::
    4.0.0 NetBSD no longer has *read_time* and *write_time* fields.

Network

.. function:: net_io_counters(pernic=False)

  Return system-wide network I/O statistics as a named tuple including the
  following attributes:

  - **bytes_sent**: number of bytes sent
  - **bytes_recv**: number of bytes received
  - **packets_sent**: number of packets sent
  - **packets_recv**: number of packets received
  - **errin**: total number of errors while receiving
  - **errout**: total number of errors while sending
  - **dropin**: total number of incoming packets which were dropped
  - **dropout**: total number of outgoing packets which were dropped (always 0
    on OSX and BSD)

  If *pernic* is ``True`` return the same information for every network
  interface installed on the system as a dictionary with network interface
  names as the keys and the named tuple described above as the values.
  On some systems such as Linux, on a very busy or long-lived system, the
  numbers returned by the kernel may overflow and wrap (restart from zero).
  If *nowrap* is ``True`` psutil will detect and adjust those numbers across
  function calls and add "old value" to "new value" so that the returned
  numbers will always be increasing or remain the same, but never decrease.
  ``net_io_counters.cache_clear()`` can be used to invalidate the *nowrap*
  cache.

    >>> import psutil
    >>> psutil.net_io_counters()
    snetio(bytes_sent=14508483, bytes_recv=62749361, packets_sent=84311, packets_recv=94888, errin=0, errout=0, dropin=0, dropout=0)
    >>>
    >>> psutil.net_io_counters(pernic=True)
    {'lo': snetio(bytes_sent=547971, bytes_recv=547971, packets_sent=5075, packets_recv=5075, errin=0, errout=0, dropin=0, dropout=0),
    'wlan0': snetio(bytes_sent=13921765, bytes_recv=62162574, packets_sent=79097, packets_recv=89648, errin=0, errout=0, dropin=0, dropout=0)}

  Also see `nettop.py <https://github.com/giampaolo/psutil/blob/master/scripts/nettop.py>`__
  and `ifconfig.py <https://github.com/giampaolo/psutil/blob/master/scripts/ifconfig.py>`__
  for an example application.

  .. versionchanged::
    5.3.0 numbers no longer wrap (restart from zero) across calls thanks to new
    *nowrap* argument.

.. function:: net_connections(kind='inet')

  Return system-wide socket connections as a list of named tuples.
  Every named tuple provides 7 attributes:

  - **fd**: the socket file descriptor. If the connection refers to the current
    process this may be passed to
    `socket.fromfd() <http://docs.python.org/library/socket.html#socket.fromfd>`__
    to obtain a usable socket object.
    On Windows and SunOS this is always set to ``-1``.
  - **family**: the address family, either `AF_INET
    <http://docs.python.org//library/socket.html#socket.AF_INET>`__,
    `AF_INET6 <http://docs.python.org//library/socket.html#socket.AF_INET6>`__
    or `AF_UNIX <http://docs.python.org//library/socket.html#socket.AF_UNIX>`__.
  - **type**: the address type, either `SOCK_STREAM
    <http://docs.python.org//library/socket.html#socket.SOCK_STREAM>`__ or
    `SOCK_DGRAM
    <http://docs.python.org//library/socket.html#socket.SOCK_DGRAM>`__.
  - **laddr**: the local address as a ``(ip, port)`` named tuple or a ``path``
    in case of AF_UNIX sockets. For UNIX sockets see notes below.
  - **raddr**: the remote address as a ``(ip, port)`` named tuple or an
    absolute ``path`` in case of UNIX sockets.
    When the remote endpoint is not connected you'll get an empty tuple
    (AF_INET*) or ``""`` (AF_UNIX). For UNIX sockets see notes below.
  - **status**: represents the status of a TCP connection. The return value
    is one of the :data:`psutil.CONN_* <psutil.CONN_ESTABLISHED>` constants
    (a string).
    For UDP and UNIX sockets this is always going to be
    :const:`psutil.CONN_NONE`.
  - **pid**: the PID of the process which opened the socket, if retrievable,
    else ``None``. On some platforms (e.g. Linux) the availability of this
    field changes depending on process privileges (root is needed).

  The *kind* parameter is a string which filters for connections matching the
  following criteria:

  .. table::

   +----------------+-----------------------------------------------------+
   | **Kind value** | **Connections using**                               |
   +================+=====================================================+
   | ``"inet"``     | IPv4 and IPv6                                       |
   +----------------+-----------------------------------------------------+
   | ``"inet4"``    | IPv4                                                |
   +----------------+-----------------------------------------------------+
   | ``"inet6"``    | IPv6                                                |
   +----------------+-----------------------------------------------------+
   | ``"tcp"``      | TCP                                                 |
   +----------------+-----------------------------------------------------+
   | ``"tcp4"``     | TCP over IPv4                                       |
   +----------------+-----------------------------------------------------+
   | ``"tcp6"``     | TCP over IPv6                                       |
   +----------------+-----------------------------------------------------+
   | ``"udp"``      | UDP                                                 |
   +----------------+-----------------------------------------------------+
   | ``"udp4"``     | UDP over IPv4                                       |
   +----------------+-----------------------------------------------------+
   | ``"udp6"``     | UDP over IPv6                                       |
   +----------------+-----------------------------------------------------+
   | ``"unix"``     | UNIX socket (both UDP and TCP protocols)            |
   +----------------+-----------------------------------------------------+
   | ``"all"``      | the sum of all the possible families and protocols  |
   +----------------+-----------------------------------------------------+

  On OSX and AIX this function requires root privileges.
  To get per-process connections use :meth:`Process.connections`.
  Also, see
  `netstat.py sample script <https://github.com/giampaolo/psutil/blob/master/scripts/netstat.py>`__.
  Example:

    >>> import psutil
    >>> psutil.net_connections()
    [pconn(fd=115, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=48776), raddr=addr(ip='93.186.135.91', port=80), status='ESTABLISHED', pid=1254),
     pconn(fd=117, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=43761), raddr=addr(ip='72.14.234.100', port=80), status='CLOSING', pid=2987),
     pconn(fd=-1, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=60759), raddr=addr(ip='72.14.234.104', port=80), status='ESTABLISHED', pid=None),
     pconn(fd=-1, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=51314), raddr=addr(ip='72.14.234.83', port=443), status='SYN_SENT', pid=None)
     ...]

  .. note::
    (OSX and AIX) :class:`psutil.AccessDenied` is always raised unless running
    as root. This is a limitation of the OS and ``lsof`` does the same.

  .. note::
    (Solaris) UNIX sockets are not supported.

  .. note::
     (Linux, FreeBSD) "raddr" field for UNIX sockets is always set to "".
     This is a limitation of the OS.

  .. note::
     (OpenBSD) "laddr" and "raddr" fields for UNIX sockets are always set to
     "". This is a limitation of the OS.

  .. versionadded:: 2.1.0

  .. versionchanged:: 5.3.0 : socket "fd" is now set for real instead of being
     ``-1``.

  .. versionchanged:: 5.3.0 : "laddr" and "raddr" are named tuples.

.. function:: net_if_addrs()

  Return the addresses associated to each NIC (network interface card)
  installed on the system as a dictionary whose keys are the NIC names and
  value is a list of named tuples for each address assigned to the NIC.
  Each named tuple includes 5 fields:

  - **family**: the address family, either
    `AF_INET <http://docs.python.org//library/socket.html#socket.AF_INET>`__,
    `AF_INET6 <http://docs.python.org//library/socket.html#socket.AF_INET6>`__
    or :const:`psutil.AF_LINK`, which refers to a MAC address.
  - **address**: the primary NIC address (always set).
  - **netmask**: the netmask address (may be ``None``).
  - **broadcast**: the broadcast address (may be ``None``).
  - **ptp**: stands for "point to point"; it's the destination address on a
    point to point interface (typically a VPN). *broadcast* and *ptp* are
    mutually exclusive. May be ``None``.

  Example::

    >>> import psutil
    >>> psutil.net_if_addrs()
    {'lo': [snic(family=<AddressFamily.AF_INET: 2>, address='127.0.0.1', netmask='255.0.0.0', broadcast='127.0.0.1', ptp=None),
            snic(family=<AddressFamily.AF_INET6: 10>, address='::1', netmask='ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff', broadcast=None, ptp=None),
            snic(family=<AddressFamily.AF_LINK: 17>, address='00:00:00:00:00:00', netmask=None, broadcast='00:00:00:00:00:00', ptp=None)],
     'wlan0': [snic(family=<AddressFamily.AF_INET: 2>, address='192.168.1.3', netmask='255.255.255.0', broadcast='192.168.1.255', ptp=None),
               snic(family=<AddressFamily.AF_INET6: 10>, address='fe80::c685:8ff:fe45:641%wlan0', netmask='ffff:ffff:ffff:ffff::', broadcast=None, ptp=None),
               snic(family=<AddressFamily.AF_LINK: 17>, address='c4:85:08:45:06:41', netmask=None, broadcast='ff:ff:ff:ff:ff:ff', ptp=None)]}
    >>>

  See also `nettop.py <https://github.com/giampaolo/psutil/blob/master/scripts/nettop.py>`__
  and `ifconfig.py <https://github.com/giampaolo/psutil/blob/master/scripts/ifconfig.py>`__
  for an example application.

  .. note::
    if you're interested in others families (e.g. AF_BLUETOOTH) you can use
    the more powerful `netifaces <https://pypi.python.org/pypi/netifaces/>`__
    extension.

  .. note::
    you can have more than one address of the same family associated with each
    interface (that's why dict values are lists).

  .. note::
    *broadcast* and *ptp* are not supported on Windows and are always ``None``.

  .. versionadded:: 3.0.0

  .. versionchanged:: 3.2.0 *ptp* field was added.

  .. versionchanged:: 4.4.0 added support for *netmask* field on Windows which
    is no longer ``None``.

.. function:: net_if_stats()

  Return information about each NIC (network interface card) installed on the
  system as a dictionary whose keys are the NIC names and value is a named tuple
  with the following fields:

  - **isup**: a bool indicating whether the NIC is up and running.
  - **duplex**: the duplex communication type;
    it can be either :const:`NIC_DUPLEX_FULL`, :const:`NIC_DUPLEX_HALF` or
    :const:`NIC_DUPLEX_UNKNOWN`.
  - **speed**: the NIC speed expressed in mega bits (MB), if it can't be
    determined (e.g. 'localhost') it will be set to ``0``.
  - **mtu**: NIC's maximum transmission unit expressed in bytes.

  Example:

    >>> import psutil
    >>> psutil.net_if_stats()
    {'eth0': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_FULL: 2>, speed=100, mtu=1500),
     'lo': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_UNKNOWN: 0>, speed=0, mtu=65536)}

  Also see `nettop.py <https://github.com/giampaolo/psutil/blob/master/scripts/nettop.py>`__
  and `ifconfig.py <https://github.com/giampaolo/psutil/blob/master/scripts/ifconfig.py>`__
  for an example application.

  .. versionadded:: 3.0.0


Sensors

.. function:: sensors_temperatures(fahrenheit=False)

  Return hardware temperatures. Each entry is a named tuple representing a
  certain hardware temperature sensor (it may be a CPU, an hard disk or
  something else, depending on the OS and its configuration).
  All temperatures are expressed in celsius unless *fahrenheit* is set to
  ``True``.
  If sensors are not supported by the OS an empty dict is returned.
  Example::

    >>> import psutil
    >>> psutil.sensors_temperatures()
    {'acpitz': [shwtemp(label='', current=47.0, high=103.0, critical=103.0)],
     'asus': [shwtemp(label='', current=47.0, high=None, critical=None)],
     'coretemp': [shwtemp(label='Physical id 0', current=52.0, high=100.0, critical=100.0),
                  shwtemp(label='Core 0', current=45.0, high=100.0, critical=100.0),
                  shwtemp(label='Core 1', current=52.0, high=100.0, critical=100.0),
                  shwtemp(label='Core 2', current=45.0, high=100.0, critical=100.0),
                  shwtemp(label='Core 3', current=47.0, high=100.0, critical=100.0)]}

  See also `temperatures.py <https://github.com/giampaolo/psutil/blob/master/scripts/temperatures.py>`__ and `sensors.py <https://github.com/giampaolo/psutil/blob/master/scripts/sensors.py>`__
  for an example application.

  Availability: Linux

  .. versionadded:: 5.1.0

  .. warning::

    this API is experimental. Backward incompatible changes may occur if
    deemed necessary.

.. function:: sensors_fans()

  Return hardware fans speed. Each entry is a named tuple representing a
  certain hardware sensor fan.
  Fan speed is expressed in RPM (rounds per minute).
  If sensors are not supported by the OS an empty dict is returned.
  Example::

    >>> import psutil
    >>> psutil.sensors_fans()
    {'asus': [sfan(label='cpu_fan', current=3200)]}

  See also `fans.py <https://github.com/giampaolo/psutil/blob/master/scripts/fans.py>`__  and `sensors.py <https://github.com/giampaolo/psutil/blob/master/scripts/sensors.py>`__
  for an example application.

  Availability: Linux

  .. versionadded:: 5.2.0

  .. warning::

    this API is experimental. Backward incompatible changes may occur if
    deemed necessary.

.. function:: sensors_battery()

  Return battery status information as a named tuple including the following
  values. If no battery is installed or metrics can't be determined ``None``
  is returned.

  - **percent**: battery power left as a percentage.
  - **secsleft**: a rough approximation of how many seconds are left before the
    battery runs out of power.
    If the AC power cable is connected this is set to
    :data:`psutil.POWER_TIME_UNLIMITED <psutil.POWER_TIME_UNLIMITED>`.
    If it can't be determined it is set to
    :data:`psutil.POWER_TIME_UNKNOWN <psutil.POWER_TIME_UNKNOWN>`.
  - **power_plugged**: ``True`` if the AC power cable is connected, ``False``
    if not or ``None`` if it can't be determined.

  Example::

    >>> import psutil
    >>>
    >>> def secs2hours(secs):
    ...     mm, ss = divmod(secs, 60)
    ...     hh, mm = divmod(mm, 60)
    ...     return "%d:%02d:%02d" % (hh, mm, ss)
    ...
    >>> battery = psutil.sensors_battery()
    >>> battery
    sbattery(percent=93, secsleft=16628, power_plugged=False)
    >>> print("charge = %s%%, time left = %s" % (batt.percent, secs2hours(batt.secsleft)))
    charge = 93%, time left = 4:37:08

  See also `battery.py <https://github.com/giampaolo/psutil/blob/master/scripts/battery.py>`__  and `sensors.py <https://github.com/giampaolo/psutil/blob/master/scripts/sensors.py>`__ for an example application.

  Availability: Linux, Windows, FreeBSD

  .. versionadded:: 5.1.0

  .. warning::

    this API is experimental. Backward incompatible changes may occur if
    deemed necessary.

Other system info

.. function:: boot_time()

  Return the system boot time expressed in seconds since the epoch.
  Example:

  .. code-block:: python

     >>> import psutil, datetime
     >>> psutil.boot_time()
     1389563460.0
     >>> datetime.datetime.fromtimestamp(psutil.boot_time()).strftime("%Y-%m-%d %H:%M:%S")
     '2014-01-12 22:51:00'

  .. note::
    on Windows this function may return a time which is off by 1 second if it's
    used across different processes (see
    `issue #1007 <https://github.com/giampaolo/psutil/issues/1007>`__).

.. function:: users()

  Return users currently connected on the system as a list of named tuples
  including the following fields:

  - **user**: the name of the user.
  - **terminal**: the tty or pseudo-tty associated with the user, if any,
    else ``None``.
  - **host**: the host name associated with the entry, if any.
  - **started**: the creation time as a floating point number expressed in
    seconds since the epoch.
  - **pid**: the PID of the login process (like sshd, tmux, gdm-session-worker,
    ...). On Windows and OpenBSD this is always set to ``None``.

  Example::

    >>> import psutil
    >>> psutil.users()
    [suser(name='giampaolo', terminal='pts/2', host='localhost', started=1340737536.0, pid=1352),
     suser(name='giampaolo', terminal='pts/3', host='localhost', started=1340737792.0, pid=1788)]

  .. versionchanged::
    5.3.0 added "pid" field

Processes

Functions

.. function:: pids()

  Return a list of current running PIDs. To iterate over all processes
  and avoid race conditions :func:`process_iter()` should be preferred.

  >>> import psutil
  >>> psutil.pids()
  [1, 2, 3, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, ..., 32498]

.. function:: process_iter(attrs=None, ad_value=None)

  Return an iterator yielding a :class:`Process` class instance for all running
  processes on the local machine.
  Every instance is only created once and then cached into an internal table
  which is updated every time an element is yielded.
  Cached :class:`Process` instances are checked for identity so that you're
  safe in case a PID has been reused by another process, in which case the
  cached instance is updated.
  This is should be preferred over :func:`psutil.pids()` for iterating over
  processes.
  Sorting order in which processes are returned is
  based on their PID.
  *attrs* and *ad_value* have the same meaning as in :meth:`Process.as_dict()`.
  If *attrs* is specified :meth:`Process.as_dict()` is called interanally and
  the resulting dict is stored as a ``info`` attribute which is attached to the
  returned :class:`Process`  instances.
  If *attrs* is an empty list it will retrieve all process info (slow).
  Example usage::

    >>> import psutil
    >>> for proc in psutil.process_iter():
    ...     try:
    ...         pinfo = proc.as_dict(attrs=['pid', 'name', 'username'])
    ...     except psutil.NoSuchProcess:
    ...         pass
    ...     else:
    ...         print(pinfo)
    ...
    {'name': 'systemd', 'pid': 1, 'username': 'root'}
    {'name': 'kthreadd', 'pid': 2, 'username': 'root'}
    {'name': 'ksoftirqd/0', 'pid': 3, 'username': 'root'}
    ...

  More compact version using *attrs* parameter::

    >>> import psutil
    >>> for proc in psutil.process_iter(attrs=['pid', 'name', 'username']):
    ...     print(proc.info)
    ...
    {'name': 'systemd', 'pid': 1, 'username': 'root'}
    {'name': 'kthreadd', 'pid': 2, 'username': 'root'}
    {'name': 'ksoftirqd/0', 'pid': 3, 'username': 'root'}
    ...

  Example of a dict comprehensions to create a ``{pid: info, ...}`` data
  structure::

    >>> import psutil
    >>> procs = {p.pid: p.info for p in psutil.process_iter(attrs=['name', 'username'])}
    >>> procs
    {1: {'name': 'systemd', 'username': 'root'},
     2: {'name': 'kthreadd', 'username': 'root'},
     3: {'name': 'ksoftirqd/0', 'username': 'root'},
     ...}

  Example showing how to filter processes by name::

    >>> import psutil
    >>> [p.info for p in psutil.process_iter(attrs=['pid', 'name']) if 'python' in p.info['name']]
    [{'name': 'python3', 'pid': 21947},
     {'name': 'python', 'pid': 23835}]

  See also `process filtering <#filtering-and-sorting-processes>`__ section for
  more examples.

  .. versionchanged::
    5.3.0 added "attrs" and "ad_value" parameters.

.. function:: pid_exists(pid)

  Check whether the given PID exists in the current process list. This is
  faster than doing ``pid in psutil.pids()`` and should be preferred.

.. function:: wait_procs(procs, timeout=None, callback=None)

  Convenience function which waits for a list of :class:`Process` instances to
  terminate. Return a ``(gone, alive)`` tuple indicating which processes are
  gone and which ones are still alive. The *gone* ones will have a new
  *returncode* attribute indicating process exit status (will be ``None`` for
  processes which are not our children).
  ``callback`` is a function which gets called when one of the processes being
  waited on is terminated and a :class:`Process` instance is passed as callback
  argument).
  This tunction will return as soon as all processes terminate or when
  *timeout* occurs, if specified.
  Differently from :meth:`Process.wait` it will not raise
  :class:`TimeoutExpired` if timeout occurs.
  A typical use case may be:

  - send SIGTERM to a list of processes
  - give them some time to terminate
  - send SIGKILL to those ones which are still alive

  Example which terminates and waits all the children of this process::

    import psutil

    def on_terminate(proc):
        print("process {} terminated with exit code {}".format(proc, proc.returncode))

    procs = psutil.Process().children()
    for p in procs:
        p.terminate()
    gone, alive = psutil.wait_procs(procs, timeout=3, callback=on_terminate)
    for p in alive:
        p.kill()

Exceptions

Base exception class. All other exceptions inherit from this one.

Raised by :class:`Process` class methods when no process with the given pid is found in the current process list or when a process no longer exists. name is the name the process had before disappearing and gets set only if :meth:`Process.name()` was previously called.

This may be raised by :class:`Process` class methods when querying a zombie process on UNIX (Windows doesn't have zombie processes). Depending on the method called the OS may be able to succeed in retrieving the process information or not. Note: this is a subclass of :class:`NoSuchProcess` so if you're not interested in retrieving zombies (e.g. when using :func:`process_iter()`) you can ignore this exception and just catch :class:`NoSuchProcess`.

.. versionadded:: 3.0.0

Raised by :class:`Process` class methods when permission to perform an action is denied. "name" is the name of the process (may be None).

Raised by :meth:`Process.wait` if timeout expires and process is still alive.

Process class

Represents an OS process with the given pid. If pid is omitted current process pid (os.getpid()) is used. Raise :class:`NoSuchProcess` if pid does not exist. On Linux pid can also refer to a thread ID (the id field returned by :meth:`threads` method). When accessing methods of this class always be prepared to catch :class:`NoSuchProcess`, :class:`ZombieProcess` and :class:`AccessDenied` exceptions. hash() builtin can be used against instances of this class in order to identify a process univocally over time (the hash is determined by mixing process PID and creation time). As such it can also be used with set()s.

Note

In order to efficiently fetch more than one information about the process at the same time, make sure to use either :meth:`as_dict` or :meth:`oneshot` context manager.

Note

the way this class is bound to a process is uniquely via its PID. That means that if the process terminates and the OS reuses its PID you may end up interacting with another process. The only exceptions for which process identity is preemptively checked (via PID + creation time) is for the following methods: :meth:`nice` (set), :meth:`ionice` (set), :meth:`cpu_affinity` (set), :meth:`rlimit` (set), :meth:`children`, :meth:`parent`, :meth:`suspend` :meth:`resume`, :meth:`send_signal`, :meth:`terminate` :meth:`kill`. To prevent this problem for all other methods you can use :meth:`is_running()` before querying the process or :func:`process_iter()` in case you're iterating over all processes. It must be noted though that unless you deal with very "old" (inactive) :class:`Process` instances this will hardly represent a problem.

.. method:: oneshot()

  Utility context manager which considerably speeds up the retrieval of
  multiple process information at the same time.
  Internally different process info (e.g. :meth:`name`, :meth:`ppid`,
  :meth:`uids`, :meth:`create_time`, ...) may be fetched by using the same
  routine, but only one value is returned and the others are discarded.
  When using this context manager the internal routine is executed once (in
  the example below on :meth:`name()`) the value of interest is returned and
  the others are cached.
  The subsequent calls sharing the same internal routine will return the
  cached value.
  The cache is cleared when exiting the context manager block.
  The advice is to use this every time you retrieve more than one information
  about the process. If you're lucky, you'll get a hell of a speedup.
  Example:

  >>> import psutil
  >>> p = psutil.Process()
  >>> with p.oneshot():
  ...     p.name()  # execute internal routine once collecting multiple info
  ...     p.cpu_times()  # return cached value
  ...     p.cpu_percent()  # return cached value
  ...     p.create_time()  # return cached value
  ...     p.ppid()  # return cached value
  ...     p.status()  # return cached value
  ...
  >>>

  Here's a list of methods which can take advantage of the speedup depending
  on what platform you're on.
  In the table below horizontal emtpy rows indicate what process methods can
  be efficiently grouped together internally.
  The last column (speedup) shows an approximation of the speedup you can get
  if you call all the methods together (best case scenario).

  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | Linux                        | Windows                       | OSX                          | BSD                          | SunOS                    | AIX                      |
  +==============================+===============================+==============================+==============================+==========================+==========================+
  | :meth:`cpu_num`              | :meth:`cpu_percent`           | :meth:`cpu_percent`          | :meth:`cpu_num`              | :meth:`name`             | :meth:`name`             |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`cpu_percent`          | :meth:`cpu_times`             | :meth:`cpu_times`            | :meth:`cpu_percent`          | :meth:`cmdline`          | :meth:`cmdline`          |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`cpu_times`            | :meth:`io_counters()`         | :meth:`memory_info`          | :meth:`cpu_times`            | :meth:`create_time`      | :meth:`create_time`      |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`create_time`          | :meth:`memory_info`           | :meth:`memory_percent`       | :meth:`create_time`          |                          |                          |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`name`                 | :meth:`memory_maps`           | :meth:`num_ctx_switches`     | :meth:`gids`                 | :meth:`memory_info`      | :meth:`memory_info`      |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`ppid`                 | :meth:`num_ctx_switches`      | :meth:`num_threads`          | :meth:`io_counters`          | :meth:`memory_percent`   | :meth:`memory_percent`   |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`status`               | :meth:`num_handles`           |                              | :meth:`name`                 | :meth:`num_threads`      | :meth:`num_threads`      |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`terminal`             | :meth:`num_threads`           | :meth:`create_time`          | :meth:`memory_info`          | :meth:`ppid`             | :meth:`ppid`             |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  |                              | :meth:`username`              | :meth:`gids`                 | :meth:`memory_percent`       | :meth:`status`           | :meth:`status`           |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`gids`                 |                               | :meth:`name`                 | :meth:`num_ctx_switches`     | :meth:`terminal`         | :meth:`terminal`         |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`num_ctx_switches`     |                               | :meth:`ppid`                 | :meth:`ppid`                 |                          |                          |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`num_threads`          |                               | :meth:`status`               | :meth:`status`               | :meth:`gids`             | :meth:`gids`             |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`uids`                 |                               | :meth:`terminal`             | :meth:`terminal`             | :meth:`uids`             | :meth:`uids`             |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`username`             |                               | :meth:`uids`                 | :meth:`uids`                 | :meth:`username`         | :meth:`username`         |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  |                              |                               | :meth:`username`             | :meth:`username`             |                          |                          |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`memory_full_info`     |                               |                              |                              |                          |                          |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | :meth:`memory_maps`          |                               |                              |                              |                          |                          |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+
  | *speedup: +2.6x*             | *speedup: +1.8x / +6.5x*      | *speedup: +1.9x*             | *speedup: +2.0x*             | *speedup: +1.3x*         | *speedup: +1.3x*         |
  +------------------------------+-------------------------------+------------------------------+------------------------------+--------------------------+--------------------------+

  .. versionadded:: 5.0.0

.. attribute:: pid

   The process PID. This is the only (read-only) attribute of the class.

.. method:: ppid()

  The process parent PID.  On Windows the return value is cached after first
  call. Not on POSIX because
  `ppid may change <https://github.com/giampaolo/psutil/issues/321>`__
  if process becomes a zombie.
  See also :meth:`parent` method.

.. method:: name()

  The process name.  On Windows the return value is cached after first
  call. Not on POSIX because the process name
  `may change <https://github.com/giampaolo/psutil/issues/692>`__.
  See also how to `find a process by name <#find-process-by-name>`__.

.. method:: exe()

  The process executable as an absolute path.
  On some systems this may also be an empty string.
  The return value is cached after first call.

  >>> import psutil
  >>> psutil.Process().exe()
  '/usr/bin/python2.7'

.. method:: cmdline()

  The command line this process has been called with as a list of strings.
  The return value is not cached because the cmdline of a process may change.

  >>> import psutil
  >>> psutil.Process().cmdline()
  ['python', 'manage.py', 'runserver']

.. method:: environ()

  The environment variables of the process as a dict.  Note: this might not
  reflect changes made after the process started.

  >>> import psutil
  >>> psutil.Process().environ()
  {'LC_NUMERIC': 'it_IT.UTF-8', 'QT_QPA_PLATFORMTHEME': 'appmenu-qt5', 'IM_CONFIG_PHASE': '1', 'XDG_GREETER_DATA_DIR': '/var/lib/lightdm-data/giampaolo', 'GNOME_DESKTOP_SESSION_ID': 'this-is-deprecated', 'XDG_CURRENT_DESKTOP': 'Unity', 'UPSTART_EVENTS': 'started starting', 'GNOME_KEYRING_PID': '', 'XDG_VTNR': '7', 'QT_IM_MODULE': 'ibus', 'LOGNAME': 'giampaolo', 'USER': 'giampaolo', 'PATH': '/home/giampaolo/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/snap/bin:/home/giampaolo/svn/sysconf/bin', 'LC_PAPER': 'it_IT.UTF-8', 'GNOME_KEYRING_CONTROL': '', 'GTK_IM_MODULE': 'ibus', 'DISPLAY': ':0', 'LANG': 'en_US.UTF-8', 'LESS_TERMCAP_se': '\x1b[0m', 'TERM': 'xterm-256color', 'SHELL': '/bin/bash', 'XDG_SESSION_PATH': '/org/freedesktop/DisplayManager/Session0', 'XAUTHORITY': '/home/giampaolo/.Xauthority', 'LANGUAGE': 'en_US', 'COMPIZ_CONFIG_PROFILE': 'ubuntu', 'LC_MONETARY': 'it_IT.UTF-8', 'QT_LINUX_ACCESSIBILITY_ALWAYS_ON': '1', 'LESS_TERMCAP_me': '\x1b[0m', 'LESS_TERMCAP_md': '\x1b[01;38;5;74m', 'LESS_TERMCAP_mb': '\x1b[01;31m', 'HISTSIZE': '100000', 'UPSTART_INSTANCE': '', 'CLUTTER_IM_MODULE': 'xim', 'WINDOWID': '58786407', 'EDITOR': 'vim', 'SESSIONTYPE': 'gnome-session', 'XMODIFIERS': '@im=ibus', 'GPG_AGENT_INFO': '/home/giampaolo/.gnupg/S.gpg-agent:0:1', 'HOME': '/home/giampaolo', 'HISTFILESIZE': '100000', 'QT4_IM_MODULE': 'xim', 'GTK2_MODULES': 'overlay-scrollbar', 'XDG_SESSION_DESKTOP': 'ubuntu', 'SHLVL': '1', 'XDG_RUNTIME_DIR': '/run/user/1000', 'INSTANCE': 'Unity', 'LC_ADDRESS': 'it_IT.UTF-8', 'SSH_AUTH_SOCK': '/run/user/1000/keyring/ssh', 'VTE_VERSION': '4205', 'GDMSESSION': 'ubuntu', 'MANDATORY_PATH': '/usr/share/gconf/ubuntu.mandatory.path', 'VISUAL': 'vim', 'DESKTOP_SESSION': 'ubuntu', 'QT_ACCESSIBILITY': '1', 'XDG_SEAT_PATH': '/org/freedesktop/DisplayManager/Seat0', 'LESSCLOSE': '/usr/bin/lesspipe %s %s', 'LESSOPEN': '| /usr/bin/lesspipe %s', 'XDG_SESSION_ID': 'c2', 'DBUS_SESSION_BUS_ADDRESS': 'unix:abstract=/tmp/dbus-9GAJpvnt8r', '_': '/usr/bin/python', 'DEFAULTS_PATH': '/usr/share/gconf/ubuntu.default.path', 'LC_IDENTIFICATION': 'it_IT.UTF-8', 'LESS_TERMCAP_ue': '\x1b[0m', 'UPSTART_SESSION': 'unix:abstract=/com/ubuntu/upstart-session/1000/1294', 'XDG_CONFIG_DIRS': '/etc/xdg/xdg-ubuntu:/usr/share/upstart/xdg:/etc/xdg', 'GTK_MODULES': 'gail:atk-bridge:unity-gtk-module', 'XDG_SESSION_TYPE': 'x11', 'PYTHONSTARTUP': '/home/giampaolo/.pythonstart', 'LC_NAME': 'it_IT.UTF-8', 'OLDPWD': '/home/giampaolo/svn/curio_giampaolo/tests', 'GDM_LANG': 'en_US', 'LC_TELEPHONE': 'it_IT.UTF-8', 'HISTCONTROL': 'ignoredups:erasedups', 'LC_MEASUREMENT': 'it_IT.UTF-8', 'PWD': '/home/giampaolo/svn/curio_giampaolo', 'JOB': 'gnome-session', 'LESS_TERMCAP_us': '\x1b[04;38;5;146m', 'UPSTART_JOB': 'unity-settings-daemon', 'LC_TIME': 'it_IT.UTF-8', 'LESS_TERMCAP_so': '\x1b[38;5;246m', 'PAGER': 'less', 'XDG_DATA_DIRS': '/usr/share/ubuntu:/usr/share/gnome:/usr/local/share/:/usr/share/:/var/lib/snapd/desktop', 'XDG_SEAT': 'seat0'}

  Availability: Linux, OSX, Windows, SunOS

  .. versionadded:: 4.0.0
  .. versionchanged:: 5.3.0 added SunOS support

.. method:: create_time()

  The process creation time as a floating point number expressed in seconds
  since the epoch, in
  `UTC <http://en.wikipedia.org/wiki/Coordinated_universal_time>`__.
  The return value is cached after first call.

    >>> import psutil, datetime
    >>> p = psutil.Process()
    >>> p.create_time()
    1307289803.47
    >>> datetime.datetime.fromtimestamp(p.create_time()).strftime("%Y-%m-%d %H:%M:%S")
    '2011-03-05 18:03:52'

.. method:: as_dict(attrs=None, ad_value=None)

  Utility method retrieving multiple process information as a dictionary.
  If *attrs* is specified it must be a list of strings reflecting available
  :class:`Process` class's attribute names (e.g. ``['cpu_times', 'name']``),
  else all public (read only) attributes are assumed. *ad_value* is the
  value which gets assigned to a dict key in case :class:`AccessDenied`
  or :class:`ZombieProcess` exception is raised when retrieving that
  particular process information.
  Internally, :meth:`as_dict` uses :meth:`oneshot` context manager so
  there's no need you use it also.

    >>> import psutil
    >>> p = psutil.Process()
    >>> p.as_dict(attrs=['pid', 'name', 'username'])
    {'username': 'giampaolo', 'pid': 12366, 'name': 'python'}

  .. versionchanged::
    3.0.0 *ad_value* is used also when incurring into
    :class:`ZombieProcess` exception, not only :class:`AccessDenied`

   .. versionchanged:: 4.5.0 :meth:`as_dict` is considerably faster thanks
      to :meth:`oneshot` context manager.

.. method:: parent()

  Utility method which returns the parent process as a :class:`Process`
  object preemptively checking whether PID has been reused. If no parent
  PID is known return ``None``.
  See also :meth:`ppid` method.

.. method:: status()

  The current process status as a string. The returned string is one of the
  :data:`psutil.STATUS_*<psutil.STATUS_RUNNING>` constants.

.. method:: cwd()

  The process current working directory as an absolute path.

.. method:: username()

  The name of the user that owns the process. On UNIX this is calculated by
  using real process uid.

.. method:: uids()

  The real, effective and saved user ids of this process as a
  named tuple. This is the same as
  `os.getresuid() <http://docs.python.org//library/os.html#os.getresuid>`__
  but can be used for any process PID.

  Availability: UNIX

.. method:: gids()

  The real, effective and saved group ids of this process as a
  named tuple. This is the same as
  `os.getresgid() <http://docs.python.org//library/os.html#os.getresgid>`__
  but can be used for any process PID.

  Availability: UNIX

.. method:: terminal()

  The terminal associated with this process, if any, else ``None``. This is
  similar to "tty" command but can be used for any process PID.

  Availability: UNIX

.. method:: nice(value=None)

  Get or set process
  `niceness <blogs.techrepublic.com.com/opensource/?p=140>`__ (priority).
  On UNIX this is a number which usually goes from ``-20`` to ``20``.
  The higher the nice value, the lower the priority of the process.

    >>> import psutil
    >>> p = psutil.Process()
    >>> p.nice(10)  # set
    >>> p.nice()  # get
    10
    >>>

  Starting from `Python 3.3 <http://bugs.python.org/issue10784>`__ this
  functionality is also available as
  `os.getpriority() <http://docs.python.org/3/library/os.html#os.getpriority>`__
  and
  `os.setpriority() <http://docs.python.org/3/library/os.html#os.setpriority>`__
  (UNIX only).
  On Windows this is implemented via
  `GetPriorityClass <http://msdn.microsoft.com/en-us/library/ms683211(v=vs.85).aspx>`__
  and `SetPriorityClass <http://msdn.microsoft.com/en-us/library/ms686219(v=vs.85).aspx>`__
  Windows APIs and *value* is one of the
  :data:`psutil.*_PRIORITY_CLASS <psutil.ABOVE_NORMAL_PRIORITY_CLASS>`
  constants reflecting the MSDN documentation.
  Example which increases process priority on Windows:

    >>> p.nice(psutil.HIGH_PRIORITY_CLASS)

.. method:: ionice(ioclass=None, value=None)

  Get or set
  `process I/O niceness <http://friedcpu.wordpress.com/2007/07/17/why-arent-you-using-ionice-yet/>`__ (priority).
  On Linux *ioclass* is one of the
  :data:`psutil.IOPRIO_CLASS_*<psutil.IOPRIO_CLASS_NONE>` constants.
  *value* is a number which goes from  ``0`` to ``7``. The higher the value,
  the lower the I/O priority of the process. On Windows only *ioclass* is
  used and it can be set to ``2`` (normal), ``1`` (low) or ``0`` (very low).
  The example below sets IDLE priority class for the current process,
  meaning it will only get I/O time when no other process needs the disk:

    >>> import psutil
    >>> p = psutil.Process()
    >>> p.ionice(psutil.IOPRIO_CLASS_IDLE)  # set
    >>> p.ionice()  # get
    pionice(ioclass=<IOPriority.IOPRIO_CLASS_IDLE: 3>, value=0)
    >>>

  On Windows only *ioclass* is used and it can be set to ``2`` (normal),
  ``1`` (low) or ``0`` (very low). Also it returns an integer instead of a
  named tuple.

  Availability: Linux and Windows > Vista

  .. versionchanged::
    3.0.0 on Python >= 3.4 the returned ``ioclass`` constant is an
    `enum <https://docs.python.org/3/library/enum.html#module-enum>`__
    instead of a plain integer.

.. method:: rlimit(resource, limits=None)

  Get or set process resource limits (see
  `man prlimit <http://linux.die.net/man/2/prlimit>`__). *resource* is one
  of the :data:`psutil.RLIMIT_* <psutil.RLIM_INFINITY>` constants.
  *limits* is a ``(soft, hard)`` tuple.
  This is the same as `resource.getrlimit() <http://docs.python.org/library/resource.html#resource.getrlimit>`__
  and `resource.setrlimit() <http://docs.python.org/library/resource.html#resource.setrlimit>`__
  but can be used for any process PID, not only
  `os.getpid() <http://docs.python.org/library/os.html#os.getpid>`__.
  For get, return value is a ``(soft, hard)`` tuple. Each value may be either
  and integer or :data:`psutil.RLIMIT_* <psutil.RLIM_INFINITY>`.
  Example:

    >>> import psutil
    >>> p = psutil.Process()
    >>> # process may open no more than 128 file descriptors
    >>> p.rlimit(psutil.RLIMIT_NOFILE, (128, 128))
    >>> # process may create files no bigger than 1024 bytes
    >>> p.rlimit(psutil.RLIMIT_FSIZE, (1024, 1024))
    >>> # get
    >>> p.rlimit(psutil.RLIMIT_FSIZE)
    (1024, 1024)
    >>>

  Availability: Linux

.. method:: io_counters()

  Return process I/O statistics as a named tuple.
  For Linux you can refer to
  `/proc filesysem documentation <http://stackoverflow.com/a/3634088>`__.

  - **read_count**: the number of read operations performed (cumulative).
    This is supposed to count the number of read-related syscalls such as
    ``read()`` and ``pread()`` on UNIX.
  - **write_count**: the number of write operations performed (cumulative).
    This is supposed to count the number of write-related syscalls such as
    ``write()`` and ``pwrite()`` on UNIX.
  - **read_bytes**: the number of bytes read (cumulative).
    Always ``-1`` on  BSD.
  - **write_bytes**: the number of bytes written (cumulative).
    Always ``-1`` on  BSD.

  Linux specific:

  - **read_chars** *(Linux)*: the amount of bytes which this process passed
    to ``read()`` and ``pread()`` syscalls (cumulative).
    Differently from *read_bytes* it doesn't care whether or not actual
    physical disk I/O occurred.
  - **write_chars** *(Linux)*: the amount of bytes which this process passed
    to ``write()`` and ``pwrite()`` syscalls (cumulative).
    Differently from *write_bytes* it doesn't care whether or not actual
    physical disk I/O occurred.

  Windows specific:

  - **other_count** *(Windows)*: the number of I/O operations performed
    other than read and write operations.
  - **other_bytes** *(Windows)*: the number of bytes transferred during
    operations other than read and write operations.

  >>> import psutil
  >>> p = psutil.Process()
  >>> p.io_counters()
  pio(read_count=454556, write_count=3456, read_bytes=110592, write_bytes=0, read_chars=769931, write_chars=203)

  Availability: Linux, BSD, Windows, AIX

  .. versionchanged:: 5.2.0 added *read_chars* and *write_chars* on Linux;
    added *other_count* and *other_bytes* on Windows.

.. method:: num_ctx_switches()

  The number voluntary and involuntary context switches performed by
  this process (cumulative).

  .. versionchanged:: 5.4.1 added AIX support

.. method:: num_fds()

  The number of file descriptors currently opened by this process
  (non cumulative).

  Availability: UNIX

.. method:: num_handles()

  The number of handles currently used by this process (non cumulative).

  Availability: Windows

.. method:: num_threads()

  The number of threads currently used by this process (non cumulative).

.. method:: threads()

  Return threads opened by process as a list of named tuples including thread
  id and thread CPU times (user/system). On OpenBSD this method requires
  root privileges.

.. method:: cpu_times()

  Return a `(user, system, children_user, children_system)` named tuple
  representing the accumulated process time, in seconds (see
  `explanation <http://stackoverflow.com/questions/556405/>`__).
  On Windows and OSX only *user* and *system* are filled, the others are
  set to ``0``.
  This is similar to
  `os.times() <http://docs.python.org//library/os.html#os.times>`__
  but can be used for any process PID.

  .. versionchanged::
    4.1.0 return two extra fields: *children_user* and *children_system*.

.. method:: cpu_percent(interval=None)

  Return a float representing the process CPU utilization as a percentage
  which can also be ``> 100.0`` in case of a process running multiple threads
  on different CPUs.
  When *interval* is > ``0.0`` compares process times to system CPU times
  elapsed before and after the interval (blocking). When interval is ``0.0``
  or ``None`` compares process times to system CPU times elapsed since last
  call, returning immediately. That means the first time this is called it
  will return a meaningless ``0.0`` value which you are supposed to ignore.
  In this case is recommended for accuracy that this function be called a
  second time with at least ``0.1`` seconds between calls.
  Example:

    >>> import psutil
    >>> p = psutil.Process()
    >>> # blocking
    >>> p.cpu_percent(interval=1)
    2.0
    >>> # non-blocking (percentage since last call)
    >>> p.cpu_percent(interval=None)
    2.9

  .. note::
    the returned value can be > 100.0 in case of a process running multiple
    threads on different CPU cores.

  .. note::
    the returned value is explicitly *not* split evenly between all available
    CPUs (differently from :func:`psutil.cpu_percent()`).
    This means that a busy loop process running on a system with 2 logical
    CPUs will be reported as having 100% CPU utilization instead of 50%.
    This was done in order to be consistent with ``top`` UNIX utility
    and also to make it easier to identify processes hogging CPU resources
    independently from the number of CPUs.
    It must be noted that ``taskmgr.exe`` on Windows does not behave like
    this (it would report 50% usage instead).
    To emulate Windows ``taskmgr.exe`` behavior you can do:
    ``p.cpu_percent() / psutil.cpu_count()``.

  .. warning::
    the first time this method is called with interval = ``0.0`` or
    ``None`` it will return a meaningless ``0.0`` value which you are
    supposed to ignore.

.. method:: cpu_affinity(cpus=None)

  Get or set process current
  `CPU affinity <http://www.linuxjournal.com/article/6799?page=0,0>`__.
  CPU affinity consists in telling the OS to run a process on a limited set
  of CPUs only (on Linux cmdline, ``taskset`` command is typically used).
  If no argument is passed it returns the current CPU affinity as a list
  of integers.
  If passed it must be a list of integers specifying the new CPUs affinity.
  If an empty list is passed all eligible CPUs are assumed (and set).
  On some systems such as Linux this may not necessarily mean all available
  logical CPUs as in ``list(range(psutil.cpu_count()))``).

    >>> import psutil
    >>> psutil.cpu_count()
    4
    >>> p = psutil.Process()
    >>> # get
    >>> p.cpu_affinity()
    [0, 1, 2, 3]
    >>> # set; from now on, process will run on CPU #0 and #1 only
    >>> p.cpu_affinity([0, 1])
    >>> p.cpu_affinity()
    [0, 1]
    >>> # reset affinity against all eligible CPUs
    >>> p.cpu_affinity([])

  Availability: Linux, Windows, FreeBSD

  .. versionchanged:: 2.2.0 added support for FreeBSD
  .. versionchanged:: 5.1.0 an empty list can be passed to set affinity
    against all eligible CPUs.

.. method:: cpu_num()

  Return what CPU this process is currently running on.
  The returned number should be ``<=`` :func:`psutil.cpu_count()`.
  On FreeBSD certain kernel process may return ``-1``.
  It may be used in conjunction with ``psutil.cpu_percent(percpu=True)`` to
  observe the system workload distributed across multiple CPUs as shown by
  `cpu_distribution.py <https://github.com/giampaolo/psutil/blob/master/scripts/cpu_distribution.py>`__ example script.

  Availability: Linux, FreeBSD, SunOS

  .. versionadded:: 5.1.0

.. method:: memory_info()

  Return a named tuple with variable fields depending on the platform
  representing memory information about the process.
  The "portable" fields available on all plaforms are `rss` and `vms`.
  All numbers are expressed in bytes.

  +---------+---------+-------+---------+-----+------------------------------+
  | Linux   | OSX     | BSD   | Solaris | AIX | Windows                      |
  +=========+=========+=======+=========+=====+==============================+
  | rss     | rss     | rss   | rss     | rss | rss (alias for ``wset``)     |
  +---------+---------+-------+---------+-----+------------------------------+
  | vms     | vms     | vms   | vms     | vms | vms (alias for ``pagefile``) |
  +---------+---------+-------+---------+-----+------------------------------+
  | shared  | pfaults | text  |         |     | num_page_faults              |
  +---------+---------+-------+---------+-----+------------------------------+
  | text    | pageins | data  |         |     | peak_wset                    |
  +---------+---------+-------+---------+-----+------------------------------+
  | lib     |         | stack |         |     | wset                         |
  +---------+---------+-------+---------+-----+------------------------------+
  | data    |         |       |         |     | peak_paged_pool              |
  +---------+---------+-------+---------+-----+------------------------------+
  | dirty   |         |       |         |     | paged_pool                   |
  +---------+---------+-------+---------+-----+------------------------------+
  |         |         |       |         |     | peak_nonpaged_pool           |
  +---------+---------+-------+---------+-----+------------------------------+
  |         |         |       |         |     | nonpaged_pool                |
  +---------+---------+-------+---------+-----+------------------------------+
  |         |         |       |         |     | pagefile                     |
  +---------+---------+-------+---------+-----+------------------------------+
  |         |         |       |         |     | peak_pagefile                |
  +---------+---------+-------+---------+-----+------------------------------+
  |         |         |       |         |     | private                      |
  +---------+---------+-------+---------+-----+------------------------------+

  - **rss**: aka "Resident Set Size", this is the non-swapped physical
    memory a process has used.
    On UNIX it matches "top"'s RES column
    (see `doc <http://linux.die.net/man/1/top>`__).
    On Windows this is an alias for `wset` field and it matches "Mem Usage"
    column of taskmgr.exe.

  - **vms**: aka "Virtual Memory Size", this is the total amount of virtual
    memory used by the process.
    On UNIX it matches "top"'s VIRT column
    (see `doc <http://linux.die.net/man/1/top>`__).
    On Windows this is an alias for `pagefile` field and it matches
    "Mem Usage" "VM Size" column of taskmgr.exe.

  - **shared**: *(Linux)*
    memory that could be potentially shared with other processes.
    This matches "top"'s SHR column
    (see `doc <http://linux.die.net/man/1/top>`__).

  - **text** *(Linux, BSD)*:
    aka TRS (text resident set) the amount of memory devoted to
    executable code. This matches "top"'s CODE column
    (see `doc <http://linux.die.net/man/1/top>`__).

  - **data** *(Linux, BSD)*:
    aka DRS (data resident set) the amount of physical memory devoted to
    other than executable code. It matches "top"'s DATA column
    (see `doc <http://linux.die.net/man/1/top>`__).

  - **lib** *(Linux)*: the memory used by shared libraries.

  - **dirty** *(Linux)*: the number of dirty pages.

  - **pfaults** *(OSX)*: number of page faults.

  - **pageins** *(OSX)*: number of actual pageins.

  For on explanation of Windows fields rely on
  `PROCESS_MEMORY_COUNTERS_EX <http://msdn.microsoft.com/en-us/library/windows/desktop/ms684874(v=vs.85).aspx>`__ structure doc.
  Example on Linux:

    >>> import psutil
    >>> p = psutil.Process()
    >>> p.memory_info()
    pmem(rss=15491072, vms=84025344, shared=5206016, text=2555904, lib=0, data=9891840, dirty=0)

  .. versionchanged::
    4.0.0 multiple fields are returned, not only `rss` and `vms`.

.. method:: memory_info_ex()

  Same as :meth:`memory_info` (deprecated).

  .. warning::
    deprecated in version 4.0.0; use :meth:`memory_info` instead.

.. method:: memory_full_info()

  This method returns the same information as :meth:`memory_info`, plus, on
  some platform (Linux, OSX, Windows), also provides additional metrics
  (USS, PSS and swap).
  The additional metrics provide a better representation of "effective"
  process memory consumption (in case of USS) as explained in detail in this
  `blog post <http://grodola.blogspot.com/2016/02/psutil-4-real-process-memory-and-environ.html>`__.
  It does so by passing through the whole process address.
  As such it usually requires higher user privileges than
  :meth:`memory_info` and is considerably slower.
  On platforms where extra fields are not implemented this simply returns the
  same metrics as :meth:`memory_info`.

  - **uss** *(Linux, OSX, Windows)*:
    aka "Unique Set Size", this is the memory which is unique to a process
    and which would be freed if the process was terminated right now.

  - **pss** *(Linux)*: aka "Proportional Set Size", is the amount of memory
    shared with other processes, accounted in a way that the amount is
    divided evenly between the processes that share it.
    I.e. if a process has 10 MBs all to itself and 10 MBs shared with
    another process its PSS will be 15 MBs.

  - **swap** *(Linux)*: amount of memory that has been swapped out to disk.

  .. note::
    `uss` is probably the most representative metric for determining how
    much memory is actually being used by a process.
    It represents the amount of memory that would be freed if the process
    was terminated right now.

  Example on Linux:

    >>> import psutil
    >>> p = psutil.Process()
    >>> p.memory_full_info()
    pfullmem(rss=10199040, vms=52133888, shared=3887104, text=2867200, lib=0, data=5967872, dirty=0, uss=6545408, pss=6872064, swap=0)
    >>>

  See also `procsmem.py <https://github.com/giampaolo/psutil/blob/master/scripts/procsmem.py>`__
  for an example application.

  .. versionadded:: 4.0.0

.. method:: memory_percent(memtype="rss")

  Compare process memory to total physical system memory and calculate
  process memory utilization as a percentage.
  *memtype* argument is a string that dictates what type of process memory
  you want to compare against. You can choose between the named tuple field
  names returned by :meth:`memory_info` and :meth:`memory_full_info`
  (defaults to ``"rss"``).

  .. versionchanged:: 4.0.0 added `memtype` parameter.

.. method:: memory_maps(grouped=True)

  Return process's mapped memory regions as a list of named tuples whose
  fields are variable depending on the platform.
  This method is useful to obtain a detailed representation of process
  memory usage as explained
  `here <http://bmaurer.blogspot.it/2006/03/memory-usage-with-smaps.html>`__
  (the most important value is "private" memory).
  If *grouped* is ``True`` the mapped regions with the same *path* are
  grouped together and the different memory fields are summed.  If *grouped*
  is ``False`` each mapped region is shown as a single entity and the
  named tuple will also include the mapped region's address space (*addr*)
  and permission set (*perms*).
  See `pmap.py <https://github.com/giampaolo/psutil/blob/master/scripts/pmap.py>`__
  for an example application.

  +---------------+--------------+---------+-----------+--------------+
  | Linux         |  OSX         | Windows | Solaris   | FreeBSD      |
  +===============+==============+=========+===========+==============+
  | rss           | rss          | rss     | rss       | rss          |
  +---------------+--------------+---------+-----------+--------------+
  | size          | private      |         | anonymous | private      |
  +---------------+--------------+---------+-----------+--------------+
  | pss           | swapped      |         | locked    | ref_count    |
  +---------------+--------------+---------+-----------+--------------+
  | shared_clean  | dirtied      |         |           | shadow_count |
  +---------------+--------------+---------+-----------+--------------+
  | shared_dirty  | ref_count    |         |           |              |
  +---------------+--------------+---------+-----------+--------------+
  | private_clean | shadow_depth |         |           |              |
  +---------------+--------------+---------+-----------+--------------+
  | private_dirty |              |         |           |              |
  +---------------+--------------+---------+-----------+--------------+
  | referenced    |              |         |           |              |
  +---------------+--------------+---------+-----------+--------------+
  | anonymous     |              |         |           |              |
  +---------------+--------------+---------+-----------+--------------+
  | swap          |              |         |           |              |
  +---------------+--------------+---------+-----------+--------------+

    >>> import psutil
    >>> p = psutil.Process()
    >>> p.memory_maps()
    [pmmap_grouped(path='/lib/x8664-linux-gnu/libutil-2.15.so', rss=32768, size=2125824, pss=32768, shared_clean=0, shared_dirty=0, private_clean=20480, private_dirty=12288, referenced=32768, anonymous=12288, swap=0),
     pmmap_grouped(path='/lib/x8664-linux-gnu/libc-2.15.so', rss=3821568, size=3842048, pss=3821568, shared_clean=0, shared_dirty=0, private_clean=0, private_dirty=3821568, referenced=3575808, anonymous=3821568, swap=0),
     pmmap_grouped(path='/lib/x8664-linux-gnu/libcrypto.so.0.1', rss=34124, rss=32768, size=2134016, pss=15360, shared_clean=24576, shared_dirty=0, private_clean=0, private_dirty=8192, referenced=24576, anonymous=8192, swap=0),
     pmmap_grouped(path='[heap]',  rss=32768, size=139264, pss=32768, shared_clean=0, shared_dirty=0, private_clean=0, private_dirty=32768, referenced=32768, anonymous=32768, swap=0),
     pmmap_grouped(path='[stack]', rss=2465792, size=2494464, pss=2465792, shared_clean=0, shared_dirty=0, private_clean=0, private_dirty=2465792, referenced=2277376, anonymous=2465792, swap=0),
     ...]
    >>> p.memory_maps(grouped=False)
    [pmmap_ext(addr='00400000-006ea000', perms='r-xp', path='/usr/bin/python2.7', rss=2293760, size=3055616, pss=1157120, shared_clean=2273280, shared_dirty=0, private_clean=20480, private_dirty=0, referenced=2293760, anonymous=0, swap=0),
     pmmap_ext(addr='008e9000-008eb000', perms='r--p', path='/usr/bin/python2.7', rss=8192, size=8192, pss=6144, shared_clean=4096, shared_dirty=0, private_clean=0, private_dirty=4096, referenced=8192, anonymous=4096, swap=0),
     pmmap_ext(addr='008eb000-00962000', perms='rw-p', path='/usr/bin/python2.7', rss=417792, size=487424, pss=317440, shared_clean=200704, shared_dirty=0, private_clean=16384, private_dirty=200704, referenced=417792, anonymous=200704, swap=0),
     pmmap_ext(addr='00962000-00985000', perms='rw-p', path='[anon]', rss=139264, size=143360, pss=139264, shared_clean=0, shared_dirty=0, private_clean=0, private_dirty=139264, referenced=139264, anonymous=139264, swap=0),
     pmmap_ext(addr='02829000-02ccf000', perms='rw-p', path='[heap]', rss=4743168, size=4874240, pss=4743168, shared_clean=0, shared_dirty=0, private_clean=0, private_dirty=4743168, referenced=4718592, anonymous=4743168, swap=0),
     ...]

  Availability: All platforms except OpenBSD, NetBSD and AIX.

.. method:: children(recursive=False)

  Return the children of this process as a list of :Class:`Process` objects,
  preemptively checking whether PID has been reused. If recursive is `True`
  return all the parent descendants.
  Pseudo code example assuming *A == this process*:
  ::

    A ─┐
       │
       ├─ B (child) ─┐
       │             └─ X (grandchild) ─┐
       │                                └─ Y (great grandchild)
       ├─ C (child)
       └─ D (child)

    >>> p.children()
    B, C, D
    >>> p.children(recursive=True)
    B, X, Y, C, D

  Note that in the example above if process X disappears process Y won't be
  returned either as the reference to process A is lost.
  This concept is well summaried by this
  `unit test <https://github.com/giampaolo/psutil/blob/fb9ae861cf3cf175c3da4a3cd4e558c6cbd6af91/psutil/tests/test_process.py#L1236-L1247>`__.
  See also how to `kill a process tree <#kill-process-tree>`__ and
  `terminate my children <#terminate-my-children>`__.

.. method:: open_files()

  Return regular files opened by process as a list of named tuples including
  the following fields:

  - **path**: the absolute file name.
  - **fd**: the file descriptor number; on Windows this is always ``-1``.

  Linux only:

  - **position** (*Linux*): the file (offset) position.
  - **mode** (*Linux*): a string indicating how the file was opened, similarly
    `open <https://docs.python.org/3/library/functions.html#open>`__'s
    ``mode`` argument. Possible values are ``'r'``, ``'w'``, ``'a'``,
    ``'r+'`` and ``'a+'``. There's no distinction between files opened in
    bynary or text mode (``"b"`` or ``"t"``).
  - **flags** (*Linux*): the flags which were passed to the underlying
    `os.open <https://docs.python.org/2/library/os.html#os.open>`__ C call
    when the file was opened (e.g.
    `os.O_RDONLY <https://docs.python.org/3/library/os.html#os.O_RDONLY>`__,
    `os.O_TRUNC <https://docs.python.org/3/library/os.html#os.O_TRUNC>`__,
    etc).

  >>> import psutil
  >>> f = open('file.ext', 'w')
  >>> p = psutil.Process()
  >>> p.open_files()
  [popenfile(path='/home/giampaolo/svn/psutil/file.ext', fd=3, position=0, mode='w', flags=32769)]

  .. warning::
    on Windows this method is not reliable due to some limitations of the
    underlying Windows API which may hang when retrieving certain file
    handles.
    In order to work around that psutil spawns a thread for each handle and
    kills it if it's not responding after 100ms.
    That implies that this method on Windows is not guaranteed to enumerate
    all regular file handles (see
    `issue 597 <https://github.com/giampaolo/psutil/pull/597>`_).
    Also, it will only list files living in the C:\\ drive (see
    `issue 1020 <https://github.com/giampaolo/psutil/pull/1020>`_).

  .. warning::
    on BSD this method can return files with a null path ("") due to a
    kernel bug, hence it's not reliable
    (see `issue 595 <https://github.com/giampaolo/psutil/pull/595>`_).

  .. versionchanged::
    3.1.0 no longer hangs on Windows.

  .. versionchanged::
    4.1.0 new *position*, *mode* and *flags* fields on Linux.

.. method:: connections(kind="inet")

  Return socket connections opened by process as a list of named tuples.
  To get system-wide connections use :func:`psutil.net_connections()`.
  Every named tuple provides 6 attributes:

  - **fd**: the socket file descriptor. This can be passed to
    `socket.fromfd() <http://docs.python.org/library/socket.html#socket.fromfd>`__
    to obtain a usable socket object.
    On Windows, FreeBSD and SunOS this is always set to ``-1``.
  - **family**: the address family, either `AF_INET
    <http://docs.python.org//library/socket.html#socket.AF_INET>`__,
    `AF_INET6 <http://docs.python.org//library/socket.html#socket.AF_INET6>`__
    or `AF_UNIX <http://docs.python.org//library/socket.html#socket.AF_UNIX>`__.
  - **type**: the address type, either
    `SOCK_STREAM <http://docs.python.org//library/socket.html#socket.SOCK_STREAM>`__ or
    `SOCK_DGRAM <http://docs.python.org//library/socket.html#socket.SOCK_DGRAM>`__.
  - **laddr**: the local address as a ``(ip, port)`` named tuple or a ``path``
    in case of AF_UNIX sockets. For UNIX sockets see notes below.
  - **raddr**: the remote address as a ``(ip, port)`` named tuple or an
    absolute ``path`` in case of UNIX sockets.
    When the remote endpoint is not connected you'll get an empty tuple
    (AF_INET*) or ``""`` (AF_UNIX). For UNIX sockets see notes below.
  - **status**: represents the status of a TCP connection. The return value
    is one of the :data:`psutil.CONN_* <psutil.CONN_ESTABLISHED>` constants.
    For UDP and UNIX sockets this is always going to be
    :const:`psutil.CONN_NONE`.

  The *kind* parameter is a string which filters for connections that fit the
  following criteria:

  +----------------+-----------------------------------------------------+
  | **Kind value** | **Connections using**                               |
  +================+=====================================================+
  | ``"inet"``     | IPv4 and IPv6                                       |
  +----------------+-----------------------------------------------------+
  | ``"inet4"``    | IPv4                                                |
  +----------------+-----------------------------------------------------+
  | ``"inet6"``    | IPv6                                                |
  +----------------+-----------------------------------------------------+
  | ``"tcp"``      | TCP                                                 |
  +----------------+-----------------------------------------------------+
  | ``"tcp4"``     | TCP over IPv4                                       |
  +----------------+-----------------------------------------------------+
  | ``"tcp6"``     | TCP over IPv6                                       |
  +----------------+-----------------------------------------------------+
  | ``"udp"``      | UDP                                                 |
  +----------------+-----------------------------------------------------+
  | ``"udp4"``     | UDP over IPv4                                       |
  +----------------+-----------------------------------------------------+
  | ``"udp6"``     | UDP over IPv6                                       |
  +----------------+-----------------------------------------------------+
  | ``"unix"``     | UNIX socket (both UDP and TCP protocols)            |
  +----------------+-----------------------------------------------------+
  | ``"all"``      | the sum of all the possible families and protocols  |
  +----------------+-----------------------------------------------------+

  Example:

    >>> import psutil
    >>> p = psutil.Process(1694)
    >>> p.name()
    'firefox'
    >>> p.connections()
    [pconn(fd=115, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=48776), raddr=addr(ip='93.186.135.91', port=80), status='ESTABLISHED'),
     pconn(fd=117, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=43761), raddr=addr(ip='72.14.234.100', port=80), status='CLOSING'),
     pconn(fd=119, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=60759), raddr=addr(ip='72.14.234.104', port=80), status='ESTABLISHED'),
     pconn(fd=123, family=<AddressFamily.AF_INET: 2>, type=<SocketType.SOCK_STREAM: 1>, laddr=addr(ip='10.0.0.1', port=51314), raddr=addr(ip='72.14.234.83', port=443), status='SYN_SENT')]

  .. note::
    (Solaris) UNIX sockets are not supported.

  .. note::
     (Linux, FreeBSD) "raddr" field for UNIX sockets is always set to "".
     This is a limitation of the OS.

  .. note::
     (OpenBSD) "laddr" and "raddr" fields for UNIX sockets are always set to
     "". This is a limitation of the OS.

  .. versionchanged:: 5.3.0 : "laddr" and "raddr" are named tuples.

Note

(AIX) :class:`psutil.AccessDenied` is always raised unless running as root (lsof does the same).

.. method:: is_running()

  Return whether the current process is running in the current process list.
  This is reliable also in case the process is gone and its PID reused by
  another process, therefore it must be preferred over doing
  ``psutil.pid_exists(p.pid)``.

  .. note::
    this will return ``True`` also if the process is a zombie
    (``p.status() == psutil.STATUS_ZOMBIE``).

.. method:: send_signal(signal)

  Send a signal to process (see
  `signal module <http://docs.python.org//library/signal.html>`__
  constants) preemptively checking whether PID has been reused.
  On UNIX this is the same as ``os.kill(pid, sig)``.
  On Windows only *SIGTERM*, *CTRL_C_EVENT* and *CTRL_BREAK_EVENT* signals
  are supported and *SIGTERM* is treated as an alias for :meth:`kill()`.
  See also how to `kill a process tree <#kill-process-tree>`__ and
  `terminate my children <#terminate-my-children>`__.

  .. versionchanged::
    3.2.0 support for CTRL_C_EVENT and CTRL_BREAK_EVENT signals on Windows
    was added.

.. method:: suspend()

  Suspend process execution with *SIGSTOP* signal preemptively checking
  whether PID has been reused.
  On UNIX this is the same as ``os.kill(pid, signal.SIGSTOP)``.
  On Windows this is done by suspending all process threads execution.

.. method:: resume()

  Resume process execution with *SIGCONT* signal preemptively checking
  whether PID has been reused.
  On UNIX this is the same as ``os.kill(pid, signal.SIGCONT)``.
  On Windows this is done by resuming all process threads execution.

.. method:: terminate()

  Terminate the process with *SIGTERM* signal preemptively checking
  whether PID has been reused.
  On UNIX this is the same as ``os.kill(pid, signal.SIGTERM)``.
  On Windows this is an alias for :meth:`kill`.
  See also how to `kill a process tree <#kill-process-tree>`__ and
  `terminate my children <#terminate-my-children>`__.

.. method:: kill()

  Kill the current process by using *SIGKILL* signal preemptively
  checking whether PID has been reused.
  On UNIX this is the same as ``os.kill(pid, signal.SIGKILL)``.
  On Windows this is done by using
  `TerminateProcess <http://msdn.microsoft.com/en-us/library/windows/desktop/ms686714(v=vs.85).aspx>`__.
  See also how to `kill a process tree <#kill-process-tree>`__ and
  `terminate my children <#terminate-my-children>`__.

.. method:: wait(timeout=None)

  Wait for process termination and if the process is a children of the
  current one also return the exit code, else ``None``. On Windows there's
  no such limitation (exit code is always returned). If the process is
  already terminated immediately return ``None`` instead of raising
  :class:`NoSuchProcess`. If *timeout* is specified and process is still
  alive raise :class:`TimeoutExpired` exception. It can also be used in a
  non-blocking fashion by specifying ``timeout=0`` in which case it will
  either return immediately or raise :class:`TimeoutExpired`.
  To wait for multiple processes use :func:`psutil.wait_procs()`.

  >>> import psutil
  >>> p = psutil.Process(9891)
  >>> p.terminate()
  >>> p.wait()

Popen class

A more convenient interface to stdlib subprocess.Popen. It starts a sub process and you deal with it exactly as when using subprocess.Popen but in addition it also provides all the methods of :class:`psutil.Process` class. For method names common to both classes such as :meth:`send_signal() <psutil.Process.send_signal()>`, :meth:`terminate() <psutil.Process.terminate()>` and :meth:`kill() <psutil.Process.kill()>` :class:`psutil.Process` implementation takes precedence. For a complete documentation refer to subprocess module documentation.

Note

Unlike subprocess.Popen this class preemptively checks whether PID has been reused on :meth:`send_signal() <psutil.Process.send_signal()>`, :meth:`terminate() <psutil.Process.terminate()>` and :meth:`kill() <psutil.Process.kill()>` so that you can't accidentally terminate another process, fixing http://bugs.python.org/issue6973.

>>> import psutil
>>> from subprocess import PIPE
>>>
>>> p = psutil.Popen(["/usr/bin/python", "-c", "print('hello')"], stdout=PIPE)
>>> p.name()
'python'
>>> p.username()
'giampaolo'
>>> p.communicate()
('hello\n', None)
>>> p.wait(timeout=2)
0
>>>

:class:`psutil.Popen` objects are supported as context managers via the with statement: on exit, standard file descriptors are closed, and the process is waited for. This is supported on all Python versions.

>>> import psutil, subprocess
>>> with psutil.Popen(["ifconfig"], stdout=subprocess.PIPE) as proc:
>>>     log.write(proc.stdout.read())
.. versionchanged:: 4.4.0 added context manager support

Windows services

.. function:: win_service_iter()

  Return an iterator yielding a :class:`WindowsService` class instance for all
  Windows services installed.

  .. versionadded:: 4.2.0

  Availability: Windows

.. function:: win_service_get(name)

  Get a Windows service by name, returning a :class:`WindowsService` instance.
  Raise :class:`psutil.NoSuchProcess` if no service with such name exists.

  .. versionadded:: 4.2.0

  Availability: Windows

Represents a Windows service with the given name. This class is returned by :func:`win_service_iter` and :func:`win_service_get` functions and it is not supposed to be instantiated directly.

.. method:: name()

  The service name. This string is how a service is referenced and can be
  passed to :func:`win_service_get` to get a new :class:`WindowsService`
  instance.

.. method:: display_name()

  The service display name. The value is cached when this class is
  instantiated.

.. method:: binpath()

  The fully qualified path to the service binary/exe file as a string,
  including command line arguments.

.. method:: username()

  The name of the user that owns this service.

.. method:: start_type()

  A string which can either be `"automatic"`, `"manual"` or `"disabled"`.

.. method:: pid()

  The process PID, if any, else `None`. This can be passed to
  :class:`Process` class to control the service's process.

.. method:: status()

  Service status as a string, which may be either `"running"`, `"paused"`,
  `"start_pending"`, `"pause_pending"`, `"continue_pending"`,
  `"stop_pending"` or `"stopped"`.

.. method:: description()

  Service long description.

.. method:: as_dict()

  Utility method retrieving all the information above as a dictionary.

.. versionadded:: 4.2.0

Availability: Windows

Example code:

>>> import psutil
>>> list(psutil.win_service_iter())
[<WindowsService(name='AeLookupSvc', display_name='Application Experience') at 38850096>,
 <WindowsService(name='ALG', display_name='Application Layer Gateway Service') at 38850128>,
 <WindowsService(name='APNMCP', display_name='Ask Update Service') at 38850160>,
 <WindowsService(name='AppIDSvc', display_name='Application Identity') at 38850192>,
 ...]
>>> s = psutil.win_service_get('alg')
>>> s.as_dict()
{'binpath': 'C:\\Windows\\System32\\alg.exe',
 'description': 'Provides support for 3rd party protocol plug-ins for Internet Connection Sharing',
 'display_name': 'Application Layer Gateway Service',
 'name': 'alg',
 'pid': None,
 'start_type': 'manual',
 'status': 'stopped',
 'username': 'NT AUTHORITY\\LocalService'}

Constants

.. data:: POSIX
.. data:: WINDOWS
.. data:: LINUX
.. data:: OSX
.. data:: FREEBSD
.. data:: NETBSD
.. data:: OPENBSD
.. data:: BSD
.. data:: SUNOS
.. data:: AIX

  ``bool`` constants which define what platform you're on. E.g. if on Windows,
  :const:`WINDOWS` constant will be ``True``, all others will be ``False``.

  .. versionadded:: 4.0.0
  .. versionchanged:: 5.4.0 added AIX

.. data:: PROCFS_PATH

  The path of the /proc filesystem on Linux, Solaris and AIX (defaults to
  ``"/proc"``).
  You may want to re-set this constant right after importing psutil in case
  your /proc filesystem is mounted elsewhere or if you want to retrieve
  information about Linux containers such as
  `Docker <https://www.docker.io/>`__,
  `Heroku <https://www.heroku.com/>`__ or
  `LXC <https://linuxcontainers.org/>`__ (see
  `here <https://fabiokung.com/2014/03/13/memory-inside-linux-containers/>`__
  for more info).
  It must be noted that this trick works only for APIs which rely on /proc
  filesystem (e.g. `memory`_ APIs and most :class:`Process` class methods).

  Availability: Linux, Solaris, AIX

  .. versionadded:: 3.2.3
  .. versionchanged:: 3.4.2 also available on Solaris.
  .. versionchanged:: 5.4.0 also available on AIX.

.. data:: STATUS_RUNNING
.. data:: STATUS_SLEEPING
.. data:: STATUS_DISK_SLEEP
.. data:: STATUS_STOPPED
.. data:: STATUS_TRACING_STOP
.. data:: STATUS_ZOMBIE
.. data:: STATUS_DEAD
.. data:: STATUS_WAKE_KILL
.. data:: STATUS_WAKING
.. data:: STATUS_IDLE (OSX, FreeBSD)
.. data:: STATUS_LOCKED (FreeBSD)
.. data:: STATUS_WAITING (FreeBSD)
.. data:: STATUS_SUSPENDED (NetBSD)

  A set of strings representing the status of a process.
  Returned by :meth:`psutil.Process.status()`.

  .. versionadded:: 3.4.1 STATUS_SUSPENDED (NetBSD)

.. data:: CONN_ESTABLISHED
.. data:: CONN_SYN_SENT
.. data:: CONN_SYN_RECV
.. data:: CONN_FIN_WAIT1
.. data:: CONN_FIN_WAIT2
.. data:: CONN_TIME_WAIT
.. data:: CONN_CLOSE
.. data:: CONN_CLOSE_WAIT
.. data:: CONN_LAST_ACK
.. data:: CONN_LISTEN
.. data:: CONN_CLOSING
.. data:: CONN_NONE
.. data:: CONN_DELETE_TCB (Windows)
.. data:: CONN_IDLE (Solaris)
.. data:: CONN_BOUND (Solaris)

  A set of strings representing the status of a TCP connection.
  Returned by :meth:`psutil.Process.connections()` (`status` field).

.. data:: ABOVE_NORMAL_PRIORITY_CLASS
.. data:: BELOW_NORMAL_PRIORITY_CLASS
.. data:: HIGH_PRIORITY_CLASS
.. data:: IDLE_PRIORITY_CLASS
.. data:: NORMAL_PRIORITY_CLASS
.. data:: REALTIME_PRIORITY_CLASS

  A set of integers representing the priority of a process on Windows (see
  `MSDN documentation <http://msdn.microsoft.com/en-us/library/ms686219(v=vs.85).aspx>`__).
  They can be used in conjunction with
  :meth:`psutil.Process.nice()` to get or set process priority.

  Availability: Windows

  .. versionchanged::
    3.0.0 on Python >= 3.4 these constants are
    `enums <https://docs.python.org/3/library/enum.html#module-enum>`__
    instead of a plain integer.

.. data:: IOPRIO_CLASS_NONE
.. data:: IOPRIO_CLASS_RT
.. data:: IOPRIO_CLASS_BE
.. data:: IOPRIO_CLASS_IDLE

  A set of integers representing the I/O priority of a process on Linux. They
  can be used in conjunction with :meth:`psutil.Process.ionice()` to get or set
  process I/O priority.
  *IOPRIO_CLASS_NONE* and *IOPRIO_CLASS_BE* (best effort) is the default for
  any process that hasn't set a specific I/O priority.
  *IOPRIO_CLASS_RT* (real time) means the process is given first access to the
  disk, regardless of what else is going on in the system.
  *IOPRIO_CLASS_IDLE* means the process will get I/O time when no-one else
  needs the disk.
  For further information refer to manuals of
  `ionice <http://linux.die.net/man/1/ionice>`__
  command line utility or
  `ioprio_get <http://linux.die.net/man/2/ioprio_get>`__
  system call.

  Availability: Linux

  .. versionchanged::
    3.0.0 on Python >= 3.4 these constants are
    `enums <https://docs.python.org/3/library/enum.html#module-enum>`__
    instead of a plain integer.

.. data:: RLIM_INFINITY
.. data:: RLIMIT_AS
.. data:: RLIMIT_CORE
.. data:: RLIMIT_CPU
.. data:: RLIMIT_DATA
.. data:: RLIMIT_FSIZE
.. data:: RLIMIT_LOCKS
.. data:: RLIMIT_MEMLOCK
.. data:: RLIMIT_MSGQUEUE
.. data:: RLIMIT_NICE
.. data:: RLIMIT_NOFILE
.. data:: RLIMIT_NPROC
.. data:: RLIMIT_RSS
.. data:: RLIMIT_RTPRIO
.. data:: RLIMIT_RTTIME
.. data:: RLIMIT_SIGPENDING
.. data:: RLIMIT_STACK

  Constants used for getting and setting process resource limits to be used in
  conjunction with :meth:`psutil.Process.rlimit()`. See
  `man prlimit <http://linux.die.net/man/2/prlimit>`__ for further information.

  Availability: Linux

.. data:: AF_LINK

  Constant which identifies a MAC address associated with a network interface.
  To be used in conjunction with :func:`psutil.net_if_addrs()`.

  .. versionadded:: 3.0.0

.. data:: NIC_DUPLEX_FULL
.. data:: NIC_DUPLEX_HALF
.. data:: NIC_DUPLEX_UNKNOWN

  Constants which identifies whether a NIC (network interface card) has full or
  half mode speed.  NIC_DUPLEX_FULL means the NIC is able to send and receive
  data (files) simultaneously, NIC_DUPLEX_FULL means the NIC can either send or
  receive data at a time.
  To be used in conjunction with :func:`psutil.net_if_stats()`.

  .. versionadded:: 3.0.0

.. data:: POWER_TIME_UNKNOWN
.. data:: POWER_TIME_UNLIMITED

  Whether the remaining time of the battery cannot be determined or is
  unlimited.
  May be assigned to :func:`psutil.sensors_battery()`'s *secsleft* field.

  .. versionadded:: 5.1.0

.. data:: version_info

  A tuple to check psutil installed version. Example:

      >>> import psutil
      >>> if psutil.version_info >= (4, 5):
      ...    pass


Debug mode

In case you bump into nasty errors which look like being psutil's fault you may want to run psutil in debug mode. psutil may (or may not) print some useful message on stderr before crashing with an exception (see original motivation). To enable debug mode on UNIX:

PSUTIL_DEBUG=1 python script.py

On Windows:

set PSUTIL_DEBUG=1 && C:\python36\python.exe script.py
.. versionadded:: 5.4.2


Unicode

Starting from version 5.3.0 psutil fully supports unicode, see issue #1040. The notes below apply to any API returning a string such as :meth:`Process.exe` or :meth:`Process.cwd`, including non-filesystem related methods such as :meth:`Process.username` or :meth:`WindowsService.description`:

  • all strings are encoded by using the OS filesystem encoding (sys.getfilesystemencoding()) which varies depending on the platform (e.g. "UTF-8" on OSX, "mbcs" on Win)
  • no API call is supposed to crash with UnicodeDecodeError
  • instead, in case of badly encoded data returned by the OS, the following error handlers are used to replace the corrupted characters in the string:
    • Python 3: sys.getfilesystemencodeerrors() (PY 3.6+) or "surrogatescape" on POSIX and "replace" on Windows
    • Python 2: "replace"
  • on Python 2 all APIs return bytes (str type), never unicode
  • on Python 2, you can go back to unicode by doing:
>>> unicode(p.exe(), sys.getdefaultencoding(), errors="replace")

Example which filters processes with a funky name working with both Python 2 and 3:

# -*- coding: utf-8 -*-
import psutil, sys

PY3 = sys.version_info[0] == 2
LOOKFOR = u"ƒőő"
for proc in psutil.process_iter(attrs=['name']):
    name = proc.info['name']
    if not PY3:
        name = unicode(name, sys.getdefaultencoding(), errors="replace")
    if LOOKFOR == name:
         print("process %s found" % p)

Recipes

Follows a collection of utilities and examples which are common but not generic enough to be part of the public API.

Find process by name

Check string against :meth:`Process.name()`:

import psutil

def find_procs_by_name(name):
    "Return a list of processes matching 'name'."
    ls = []
    for p in psutil.process_iter(attrs=['name']):
        if p.info['name'] == name:
            ls.append(p)
    return ls

A bit more advanced, check string against :meth:`Process.name()`, :meth:`Process.exe()` and :meth:`Process.cmdline()`:

import os
import psutil

def find_procs_by_name(name):
    "Return a list of processes matching 'name'."
    ls = []
    for p in psutil.process_iter(attrs=["name", "exe", "cmdline"]):
        if name == p.info['name'] or \
                p.info['exe'] and os.path.basename(p.info['exe']) == name or \
                p.info['cmdline'] and p.info['cmdline'][0] == name:
            ls.append(p)
    return ls

Kill process tree

import os
import signal
import psutil

def kill_proc_tree(pid, sig=signal.SIGTERM, include_parent=True,
                   timeout=None, on_terminate=None):
    """Kill a process tree (including grandchildren) with signal
    "sig" and return a (gone, still_alive) tuple.
    "on_terminate", if specified, is a callabck function which is
    called as soon as a child terminates.
    """
    if pid == os.getpid():
        raise RuntimeError("I refuse to kill myself")
    parent = psutil.Process(pid)
    children = parent.children(recursive=True)
    if include_parent:
        children.append(parent)
    for p in children:
        p.send_signal(sig)
    gone, alive = psutil.wait_procs(children, timeout=timeout,
                                    callback=on_terminate)
    return (gone, alive)

Terminate my children

This may be useful in unit tests whenever sub-processes are started. This will help ensure that no extra children (zombies) stick around to hog resources.

import psutil

def reap_children(timeout=3):
    "Tries hard to terminate and ultimately kill all the children of this process."
    def on_terminate(proc):
        print("process {} terminated with exit code {}".format(proc, proc.returncode))

    procs = psutil.Process().children()
    # send SIGTERM
    for p in procs:
        p.terminate()
    gone, alive = psutil.wait_procs(procs, timeout=timeout, callback=on_terminate)
    if alive:
        # send SIGKILL
        for p in alive:
            print("process {} survived SIGTERM; trying SIGKILL" % p)
            p.kill()
        gone, alive = psutil.wait_procs(alive, timeout=timeout, callback=on_terminate)
        if alive:
            # give up
            for p in alive:
                print("process {} survived SIGKILL; giving up" % p)

Filtering and sorting processes

This is a collection of one-liners showing how to use :func:`process_iter()` in order to filter for processes and sort them.

Setup:

>>> import psutil
>>> from pprint import pprint as pp

Processes having "python" in their name:

>>> pp([p.info for p in psutil.process_iter(attrs=['pid', 'name']) if 'python' in p.info['name']])
[{'name': 'python3', 'pid': 21947},
 {'name': 'python', 'pid': 23835}]

Processes owned by user:

>>> import getpass
>>> pp([(p.pid, p.info['name']) for p in psutil.process_iter(attrs=['name', 'username']) if p.info['username'] == getpass.getuser()])
(16832, 'bash'),
(19772, 'ssh'),
(20492, 'python')]

Processes actively running:

>>> pp([(p.pid, p.info) for p in psutil.process_iter(attrs=['name', 'status']) if p.info['status'] == psutil.STATUS_RUNNING])
[(1150, {'name': 'Xorg', 'status': 'running'}),
 (1776, {'name': 'unity-panel-service', 'status': 'running'}),
 (20492, {'name': 'python', 'status': 'running'})]

Processes using log files:

>>> import os
>>> import psutil
>>> for p in psutil.process_iter(attrs=['name', 'open_files']):
...      for file in p.info['open_files'] or []:
...          if os.path.splitext(file.path)[1] == '.log':
...               print("%-5s %-10s %s" % (p.pid, p.info['name'][:10], file.path))
...
1510  upstart    /home/giampaolo/.cache/upstart/unity-settings-daemon.log
2174  nautilus   /home/giampaolo/.local/share/gvfs-metadata/home-ce08efac.log
2650  chrome     /home/giampaolo/.config/google-chrome/Default/data_reduction_proxy_leveldb/000003.log

Processes consuming more than 500M of memory:

>>> pp([(p.pid, p.info['name'], p.info['memory_info'].rss) for p in psutil.process_iter(attrs=['name', 'memory_info']) if p.info['memory_info'].rss > 500 * 1024 * 1024])
[(2650, 'chrome', 532324352),
 (3038, 'chrome', 1120088064),
 (21915, 'sublime_text', 615407616)]

Top 3 most memory consuming processes:

>>> pp([(p.pid, p.info) for p in sorted(psutil.process_iter(attrs=['name', 'memory_percent']), key=lambda p: p.info['memory_percent'])][-3:])
[(21915, {'memory_percent': 3.6815453247662737, 'name': 'sublime_text'}),
 (3038, {'memory_percent': 6.732935429979187, 'name': 'chrome'}),
 (3249, {'memory_percent': 8.994554843376399, 'name': 'chrome'})]

Top 3 processes which consumed the most CPU time:

>>> pp([(p.pid, p.info['name'], sum(p.info['cpu_times'])) for p in sorted(psutil.process_iter(attrs=['name', 'cpu_times']), key=lambda p: sum(p.info['cpu_times'][:2]))][-3:])
[(2721, 'chrome', 10219.73),
 (1150, 'Xorg', 11116.989999999998),
 (2650, 'chrome', 18451.97)]

Top 3 processes which caused the most I/O:

>>> pp([(p.pid, p.info['name']) for p in sorted(psutil.process_iter(attrs=['name', 'io_counters']), key=lambda p: p.info['io_counters'] and p.info['io_counters'][:2])][-3:])
[(21915, 'sublime_text'),
 (1871, 'pulseaudio'),
 (1510, 'upstart')]

Top 3 processes opening more file descriptors:

 >>> pp([(p.pid, p.info) for p in sorted(psutil.process_iter(attrs=['name', 'num_fds']), key=lambda p: p.info['num_fds'])][-3:])
[(21915, {'name': 'sublime_text', 'num_fds': 105}),
 (2721, {'name': 'chrome', 'num_fds': 185}),
 (2650, {'name': 'chrome', 'num_fds': 354})]

FAQs

  • Q: What Windows versions are supported?
  • A: From Windows Vista onwards, both 32 and 64 bit versions. Latest binary (wheel / exe) release which supports Windows 2000, XP and 2003 server is psutil 3.4.2. On such old systems psutil is no longer tested or maintained, but it can still be compiled from sources (you'll need Visual Studio) and it should "work" (more or less).

  • Q: What Python versions are supported?
  • A: From 2.6 to 3.6, both 32 and 64 bit versions. Last version supporting
    Python 2.4 and 2.5 is psutil 2.1.3. PyPy is also known to work.

  • Q: What SunOS versions are supported?
  • A: From Solaris 10 onwards.

  • Q: Why do I get :class:`AccessDenied` for certain processes?
  • A: This may happen when you query processess owned by another user, especially on OSX and Windows. Unfortunately there's not much you can do about this except running the Python process with higher privileges. On Unix you may run the the Python process as root or use the SUID bit (this is the trick used by tools such as ps and netstat). On Windows you may run the Python process as NT AUTHORITY\SYSTEM or install the Python script as a Windows service (this is the trick used by tools such as ProcessHacker).

  • Q: What about load average?
  • A: psutil does not expose any load average function as it's already available in python as os.getloadavg.

Running tests

There are two ways of running tests. If psutil is already installed use:

$ python -m psutil.tests

You can use this method as a quick way to make sure psutil fully works on your platform. If you have a copy of the source code you can also use:

$ make test

Development guide

If you plan on hacking on psutil (e.g. want to add a new feature or fix a bug) take a look at the development guide.

Timeline