监控系统信息模块psutil
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
- macOS
- 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.
Processes
Functions
psutil.
pids
()-
Return a list of current running PIDs. To iterate over all processes and avoid race conditions
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]
psutil.
process_iter
(attrs=None, ad_value=None)-
Return an iterator yielding a
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. CachedProcess
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 preferred overpsutil.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 inProcess.as_dict()
. If attrs is specifiedProcess.as_dict()
is called internally and the resulting dict is stored as ainfo
attribute which is attached to the returnedProcess
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 section for more examples.
Changed in version 5.3.0: added “attrs” and “ad_value” parameters.
psutil.
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.
psutil.
wait_procs
(procs, timeout=None, callback=None)-
Convenience function which waits for a list of
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 beNone
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 aProcess
instance is passed as callback argument). This function will return as soon as all processes terminate or when timeout(seconds) occurs. Differently fromProcess.wait()
it will not raiseTimeoutExpired
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
- class
psutil.
Error
-
Base exception class. All other exceptions inherit from this one.
- class
psutil.
NoSuchProcess
(pid, name=None, msg=None) -
Raised by
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 ifProcess.name()
was previously called.
- class
psutil.
ZombieProcess
(pid, name=None, ppid=None, msg=None) -
This may be raised by
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 ofNoSuchProcess
so if you’re not interested in retrieving zombies (e.g. when usingprocess_iter()
) you can ignore this exception and just catchNoSuchProcess
.New in version 3.0.0.
- class
psutil.
AccessDenied
(pid=None, name=None, msg=None) -
Raised by
Process
class methods when permission to perform an action is denied. “name” is the name of the process (may beNone
).
- class
psutil.
TimeoutExpired
(seconds, pid=None, name=None, msg=None) -
Raised by
Process.wait()
if timeout expires and process is still alive.
Process class
- class
psutil.
Process
(pid=None) -
Represents an OS process with the given pid. If pid is omitted current process pid (os.getpid()) is used. Raise
NoSuchProcess
if pid does not exist. On Linux pid can also refer to a thread ID (the id field returned bythreads()
method). When accessing methods of this class always be prepared to catchNoSuchProcess
,ZombieProcess
andAccessDenied
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
as_dict()
oroneshot()
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:
nice()
(set),ionice()
(set),cpu_affinity()
(set),rlimit()
(set),children()
,parent()
,suspend()
resume()
,send_signal()
,terminate()
kill()
. To prevent this problem for all other methods you can useis_running()
before querying the process orprocess_iter()
in case you’re iterating over all processes. It must be noted though that unless you deal with very “old” (inactive)Process
instances this will hardly represent a problem.oneshot
()-
Utility context manager which considerably speeds up the retrieval of multiple process information at the same time. Internally different process info (e.g.
name()
,ppid()
,uids()
,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 onname()
) 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).
New in version 5.0.0.
pid
-
The process PID. This is the only (read-only) attribute of the class.
ppid
()-
The process parent PID. On Windows the return value is cached after first call. Not on POSIX because ppid may change if process becomes a zombie. See also
parent()
method.
name
()-
The process name. On Windows the return value is cached after first call. Not on POSIX because the process name may change. See also how to find a process by name.
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'
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']
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, macOS, Windows, SunOS
New in version 4.0.0.
Changed in version 5.3.0: added SunOS support
create_time
()-
The process creation time as a floating point number expressed in seconds since the epoch, in UTC. 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'
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
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 caseAccessDenied
orZombieProcess
exception is raised when retrieving that particular process information. Internally,as_dict()
usesoneshot()
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'}
Changed in version 3.0.0: ad_value is used also when incurring into
ZombieProcess
exception, not onlyAccessDenied
parent
()-
Utility method which returns the parent process as a
Process
object preemptively checking whether PID has been reused. If no parent PID is known returnNone
. See alsoppid()
method.
status
()-
The current process status as a string. The returned string is one of the
psutil.STATUS_*
constants.
cwd
()-
The process current working directory as an absolute path.
username
()-
The name of the user that owns the process. On UNIX this is calculated by using real process uid.
uids
()-
The real, effective and saved user ids of this process as a named tuple. This is the same as os.getresuid() but can be used for any process PID.
Availability: UNIX
gids
()-
The real, effective and saved group ids of this process as a named tuple. This is the same as os.getresgid() but can be used for any process PID.
Availability: UNIX
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
nice
(value=None)-
Get or set process niceness (priority). On UNIX this is a number which usually goes from
-20
to20
. 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 this functionality is also available as os.getpriority() and os.setpriority() (UNIX only). On Windows this is implemented via GetPriorityClass and SetPriorityClass Windows APIs and value is one of the
psutil.*_PRIORITY_CLASS
constants reflecting the MSDN documentation. Example which increases process priority on Windows:>>> p.nice(psutil.HIGH_PRIORITY_CLASS)
ionice
(ioclass=None, value=None)-
Get or set process I/O niceness (priority). On Linux ioclass is one of the
psutil.IOPRIO_CLASS_*
constants. value is a number which goes from0
to7
. The higher the value, the lower the I/O priority of the process. On Windows only ioclass is used and it can be set to2
(normal),1
(low) or0
(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) or0
(very low). Also it returns an integer instead of a named tuple.Availability: Linux and Windows > Vista
Changed in version 3.0.0: on Python >= 3.4 the returned
ioclass
constant is an enum instead of a plain integer.
rlimit
(resource, limits=None)-
Get or set process resource limits (see man prlimit). resource is one of the
psutil.RLIMIT_*
constants. limits is a(soft, hard)
tuple. This is the same as resource.getrlimit() and resource.setrlimit() but can be used for any process PID, not only os.getpid(). For get, return value is a(soft, hard)
tuple. Each value may be either and integer orpsutil.RLIMIT_*
. 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
io_counters
()-
Return process I/O statistics as a named tuple. For Linux you can refer to /proc filesysem documentation.
- read_count: the number of read operations performed (cumulative). This is supposed to count the number of read-related syscalls such as
read()
andpread()
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()
andpwrite()
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()
andpread()
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()
andpwrite()
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
Changed in version 5.2.0: added read_chars and write_chars on Linux; added other_count and other_bytes on Windows.
- read_count: the number of read operations performed (cumulative). This is supposed to count the number of read-related syscalls such as
num_ctx_switches
()-
The number voluntary and involuntary context switches performed by this process (cumulative).
Changed in version 5.4.1: added AIX support
num_fds
()-
The number of file descriptors currently opened by this process (non cumulative).
Availability: UNIX
num_handles
()-
The number of handles currently used by this process (non cumulative).
Availability: Windows
num_threads
()-
The number of threads currently used by this process (non cumulative).
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.
cpu_times
()-
Return a (user, system, children_user, children_system) named tuple representing the accumulated process time, in seconds (seeexplanation). On Windows and macOS only user and system are filled, the others are set to
0
. This is similar to os.times() but can be used for any process PID.Changed in version 4.1.0: return two extra fields: children_user and children_system.
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 is0.0
orNone
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 meaningless0.0
value which you are supposed to ignore. In this case is recommended for accuracy that this function be called a second time with at least0.1
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
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 withtop
UNIX utility and also to make it easier to identify processes hogging CPU resources independently from the number of CPUs. It must be noted thattaskmgr.exe
on Windows does not behave like this (it would report 50% usage instead). To emulate Windowstaskmgr.exe
behavior you can do:p.cpu_percent() / psutil.cpu_count()
.Warning
the first time this method is called with interval =
0.0
orNone
it will return a meaningless0.0
value which you are supposed to ignore.
cpu_affinity
(cpus=None)-
Get or set process current CPU affinity. 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 inlist(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
Changed in version 2.2.0: added support for FreeBSD
Changed in version 5.1.0: an empty list can be passed to set affinity against all eligible CPUs.
cpu_num
()-
Return what CPU this process is currently running on. The returned number should be
<=
psutil.cpu_count()
. On FreeBSD certain kernel process may return-1
. It may be used in conjunction withpsutil.cpu_percent(percpu=True)
to observe the system workload distributed across multiple CPUs as shown by cpu_distribution.py example script.Availability: Linux, FreeBSD, SunOS
New in version 5.1.0.
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 macOS 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). 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). 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).
- text (Linux, BSD): aka TRS (text resident set) the amount of memory devoted to executable code. This matches “top“‘s CODE column (see doc).
- 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).
- lib (Linux): the memory used by shared libraries.
- dirty (Linux): the number of dirty pages.
- pfaults (macOS): number of page faults.
- pageins (macOS): number of actual pageins.
For on explanation of Windows fields rely on PROCESS_MEMORY_COUNTERS_EX 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)
Changed in version 4.0.0: multiple fields are returned, not only rss and vms.
memory_info_ex
()-
Same as
memory_info()
(deprecated).Warning
deprecated in version 4.0.0; use
memory_info()
instead.
memory_full_info
()-
This method returns the same information as
memory_info()
, plus, on some platform (Linux, macOS, 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. It does so by passing through the whole process address. As such it usually requires higher user privileges thanmemory_info()
and is considerably slower. On platforms where extra fields are not implemented this simply returns the same metrics asmemory_info()
.- uss (Linux, macOS, 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 for an example application.
New in version 4.0.0.
memory_percent
(memtype="rss")-
Compare process memory to total physical system memory and calculate process memory utilization as a percentage. memtypeargument 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
memory_info()
andmemory_full_info()
(defaults to"rss"
).Changed in version 4.0.0: added memtype parameter.
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 (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 isFalse
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 for an example application.Linux macOS 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.
children
(recursive=False)-
Return the children of this process as a list of
Process
instances. 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. See also how to kill a process tree and terminate my children.
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’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 C call when the file was opened (e.g. os.O_RDONLY,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). Also, it will only list files living in the C:\ drive (see issue 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).
Changed in version 3.1.0: no longer hangs on Windows.
Changed in version 4.1.0: new position, mode and flags fields on Linux.
connections
(kind="inet")-
Return socket connections opened by process as a list of named tuples. To get system-wide connections use
psutil.net_connections()
. Every named tuple provides 6 attributes:- fd: the socket file descriptor. This can be passed to 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, AF_INET6 or AF_UNIX.
- type: the address type, either SOCK_STREAM or SOCK_DGRAM.
- laddr: the local address as a
(ip, port)
named tuple or apath
in case of AF_UNIX sockets. For UNIX sockets see notes below. - raddr: the remote address as a
(ip, port)
named tuple or an absolutepath
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
psutil.CONN_*
constants. For UDP and UNIX sockets this is always going to bepsutil.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.
Note
(AIX)
psutil.AccessDenied
is always raised unless running as root (lsof does the same).Changed in version 5.3.0: : “laddr” and “raddr” are named tuples.
- fd: the socket file descriptor. This can be passed to socket.fromfd() to obtain a usable socket object. On Windows, FreeBSD and SunOS this is always set to
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
).
send_signal
(signal)-
Send a signal to process (see signal module 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 SIGTERMis treated as an alias forkill()
. See also how to kill a process tree and terminate my children.Changed in version 3.2.0: support for CTRL_C_EVENT and CTRL_BREAK_EVENT signals on Windows was added.
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.
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.
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 forkill()
. See also how to kill a process tree and terminate my children.
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. See also how to kill a process tree and terminate my children.
wait
(timeout=None)-
Wait for process termination and if the process is a child 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 returnNone
instead of raisingNoSuchProcess
. timeout is expressed in seconds. If specified and the process is still alive raiseTimeoutExpired
exception.timeout=0
can be used in non-blocking apps: it will either return immediately or raiseTimeoutExpired
. To wait for multiple processes usepsutil.wait_procs()
.>>> import psutil >>> p = psutil.Process(9891) >>> p.terminate() >>> p.wait()
Popen class
- class
psutil.
Popen
(*args, **kwargs) -
A more convenient interface to stdlib subprocess.Popen. It starts a sub process and you deal with it exactly as when usingsubprocess.Popen but in addition it also provides all the methods of
psutil.Process
class. For method names common to both classes such assend_signal()
,terminate()
andkill()
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
send_signal()
,terminate()
andkill()
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 >>>
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())
Changed in version 4.4.0: added context manager support
Windows services
psutil.
win_service_iter
()-
Return an iterator yielding a
WindowsService
class instance for all Windows services installed.New in version 4.2.0.
Availability: Windows
psutil.
win_service_get
(name)-
Get a Windows service by name, returning a
WindowsService
instance. Raisepsutil.NoSuchProcess
if no service with such name exists.New in version 4.2.0.
Availability: Windows
- class
psutil.
WindowsService
-
Represents a Windows service with the given name. This class is returned by
win_service_iter()
andwin_service_get()
functions and it is not supposed to be instantiated directly.name
()-
The service name. This string is how a service is referenced and can be passed to
win_service_get()
to get a newWindowsService
instance.
display_name
()-
The service display name. The value is cached when this class is instantiated.
binpath
()-
The fully qualified path to the service binary/exe file as a string, including command line arguments.
username
()-
The name of the user that owns this service.
start_type
()-
A string which can either be “automatic”, “manual” or “disabled”.
pid
()-
The process PID, if any, else None. This can be passed to
Process
class to control the service’s process.
status
()-
Service status as a string, which may be either “running”, “paused”, “start_pending”, “pause_pending”, “continue_pending”, “stop_pending”or “stopped”.
description
()-
Service long description.
as_dict
()-
Utility method retrieving all the information above as a dictionary.
New in version 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
psutil.
POSIX
psutil.
WINDOWS
psutil.
LINUX
psutil.
MACOS
psutil.
FREEBSD
psutil.
NETBSD
psutil.
OPENBSD
psutil.
BSD
psutil.
SUNOS
psutil.
AIX
-
bool
constants which define what platform you’re on. E.g. if on Windows,WINDOWS
constant will beTrue
, all others will beFalse
.New in version 4.0.0.
Changed in version 5.4.0: added AIX
psutil.
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, Heroku or LXC (see here for more info). It must be noted that this trick works only for APIs which rely on /proc filesystem (e.g. memory APIs and mostProcess
class methods).Availability: Linux, Solaris, AIX
New in version 3.2.3.
Changed in version 3.4.2: also available on Solaris.
Changed in version 5.4.0: also available on AIX.
psutil.
STATUS_RUNNING
psutil.
STATUS_SLEEPING
psutil.
STATUS_DISK_SLEEP
psutil.
STATUS_STOPPED
psutil.
STATUS_TRACING_STOP
psutil.
STATUS_ZOMBIE
psutil.
STATUS_DEAD
psutil.
STATUS_WAKE_KILL
psutil.
STATUS_WAKING
psutil.
STATUS_PARKED
(Linux)
psutil.
STATUS_IDLE
(Linux, macOS, FreeBSD)
psutil.
STATUS_LOCKED
(FreeBSD)
psutil.
STATUS_WAITING
(FreeBSD)
psutil.
STATUS_SUSPENDED
(NetBSD)-
A set of strings representing the status of a process. Returned by
psutil.Process.status()
.New in version 3.4.1: STATUS_SUSPENDED (NetBSD)
New in version 5.4.7: STATUS_PARKED (Linux)
psutil.
CONN_ESTABLISHED
psutil.
CONN_SYN_SENT
psutil.
CONN_SYN_RECV
psutil.
CONN_FIN_WAIT1
psutil.
CONN_FIN_WAIT2
psutil.
CONN_TIME_WAIT
psutil.
CONN_CLOSE
psutil.
CONN_CLOSE_WAIT
psutil.
CONN_LAST_ACK
psutil.
CONN_LISTEN
psutil.
CONN_CLOSING
psutil.
CONN_NONE
psutil.
CONN_DELETE_TCB
(Windows)
psutil.
CONN_IDLE
(Solaris)
psutil.
CONN_BOUND
(Solaris)-
A set of strings representing the status of a TCP connection. Returned by
psutil.Process.connections()
(status field).
psutil.
ABOVE_NORMAL_PRIORITY_CLASS
psutil.
BELOW_NORMAL_PRIORITY_CLASS
psutil.
HIGH_PRIORITY_CLASS
psutil.
IDLE_PRIORITY_CLASS
psutil.
NORMAL_PRIORITY_CLASS
psutil.
REALTIME_PRIORITY_CLASS
-
A set of integers representing the priority of a process on Windows (see MSDN documentation). They can be used in conjunction with
psutil.Process.nice()
to get or set process priority.Availability: Windows
Changed in version 3.0.0: on Python >= 3.4 these constants are enums instead of a plain integer.
psutil.
IOPRIO_CLASS_NONE
psutil.
IOPRIO_CLASS_RT
psutil.
IOPRIO_CLASS_BE
psutil.
IOPRIO_CLASS_IDLE
-
A set of integers representing the I/O priority of a process on Linux. They can be used in conjunction with
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 command line utility or ioprio_get system call.Availability: Linux
Changed in version 3.0.0: on Python >= 3.4 these constants are enums instead of a plain integer.
psutil.
RLIM_INFINITY
psutil.
RLIMIT_AS
psutil.
RLIMIT_CORE
psutil.
RLIMIT_CPU
psutil.
RLIMIT_DATA
psutil.
RLIMIT_FSIZE
psutil.
RLIMIT_LOCKS
psutil.
RLIMIT_MEMLOCK
psutil.
RLIMIT_MSGQUEUE
psutil.
RLIMIT_NICE
psutil.
RLIMIT_NOFILE
psutil.
RLIMIT_NPROC
psutil.
RLIMIT_RSS
psutil.
RLIMIT_RTPRIO
psutil.
RLIMIT_RTTIME
psutil.
RLIMIT_SIGPENDING
psutil.
RLIMIT_STACK
-
Constants used for getting and setting process resource limits to be used in conjunction with
psutil.Process.rlimit()
. See man prlimitfor further information.Availability: Linux
psutil.
AF_LINK
-
Constant which identifies a MAC address associated with a network interface. To be used in conjunction with
psutil.net_if_addrs()
.New in version 3.0.0.
psutil.
NIC_DUPLEX_FULL
psutil.
NIC_DUPLEX_HALF
psutil.
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
psutil.net_if_stats()
.New in version 3.0.0.
psutil.
POWER_TIME_UNKNOWN
psutil.
POWER_TIME_UNLIMITED
-
Whether the remaining time of the battery cannot be determined or is unlimited. May be assigned to
psutil.sensors_battery()
’s secsleftfield.New in version 5.1.0.
psutil.
version_info
-
A tuple to check psutil installed version. Example:
>>> import psutil >>> if psutil.version_info >= (4, 5): ... pass
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 asProcess.exe()
or Process.cwd()
, including non-filesystem related methods such as Process.username()
or 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 macOS, “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"
- Python 3:
- on Python 2 all APIs return bytes (
str
type), neverunicode
- 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 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 Process.name()
, Process.exe()
and 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 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})]
Bytes conversion
import psutil
def bytes2human(n):
# http://code.activestate.com/recipes/578019
# >>> bytes2human(10000)
# '9.8K'
# >>> bytes2human(100001221)
# '95.4M'
symbols = ('K', 'M', 'G', 'T', 'P', 'E', 'Z', 'Y')
prefix = {}
for i, s in enumerate(symbols):
prefix[s] = 1 << (i + 1) * 10
for s in reversed(symbols):
if n >= prefix[s]:
value = float(n) / prefix[s]
return '%.1f%s' % (value, s)
return "%sB" % n
total = psutil.disk_usage('/').total
print(total)
print(bytes2human(total))
…prints:
100399730688
93.5G
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, XPand 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
AccessDenied
for certain processes? - A: This may happen when you query processess owned by another user, especially on macOS 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
andnetstat
). 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