psutil-- obtain system information of a third party Python modules

This article is excerpted Liao Xuefeng the great God Website: https://www.liaoxuefeng.com/wiki/1016959663602400/1183565811281984

 

In Python scripting to simplify the daily operation and maintenance work is an important use of Python. In Linux, there are many system commands allows us time to monitor the status of system operation, such as ps, top, freeand so on. To obtain these information systems, Python can subprocesscall and get the results module. But this is very troublesome, especially to write a lot of parsing code.

Another good way to get system information in Python is using psutilthis third-party modules. As the name suggests, psutil = process and system utilities, system monitoring can be achieved not only by one or two lines of code, you can also cross-platform, supports Linux / UNIX / OSX / Windows, is a system administrator and the operation and maintenance of small indispensable partner essential modules.

Installation psutil

If the Anaconda installation, psutil already available. Otherwise, you need to install by pip at the command line:

$ pip install psutil

Permission denied If you encounter installation fails, add sudo try again.

Get CPU information

Let's CPU to obtain information:

>>> Import psutil
 >>> psutil.cpu_count () # number of logic the CPU
 4 
>>> psutil.cpu_count (Logical = False) Physical the CPU core #
 2 
# 2 illustrates a dual-core hyper-threading, four non-core 4 is Hyper-Threading

User statistics CPU / System / Idle time:

>>> psutil.cpu_times()
scputimes(user=10963.31, nice=0.0, system=5138.67, idle=356102.45)

Then achieve a similar topcommand CPU usage, refreshed once per second, a total of 10 times:

>>> for x in range(10):
...     psutil.cpu_percent(interval=1, percpu=True)
... 
[14.0, 4.0, 4.0, 4.0]
[12.0, 3.0, 4.0, 3.0]
[8.0, 4.0, 3.0, 4.0]
[12.0, 3.0, 3.0, 3.0]
[18.8, 5.1, 5.9, 5.0]
[10.9, 5.0, 4.0, 3.0]
[12.0, 5.0, 4.0, 5.0]
[15.0, 5.0, 4.0, 4.0]
[19.0, 5.0, 5.0, 4.0]
[9.0, 3.0, 2.0, 3.0]

Get memory information

Use psutil obtain physical and swap memory information, were used:

>>> psutil.virtual_memory()
svmem(total=8589934592, available=2866520064, percent=66.6, used=7201386496, free=216178688, active=3342192640, inactive=2650341376, wired=1208852480)
>>> psutil.swap_memory()
sswap(total=1073741824, used=150732800, free=923009024, percent=14.0, sin=10705981440, sout=40353792)

Returns an integer in units of bytes, it can be seen that the total memory size 8589934592 = 8 GB, have been used 7201386496 = 6.7 GB, the use of 66.6%.

Area size is exchanged 1073741824 = 1 GB.

Get disk information

Can get disk partition, disk usage and disk IO information psutil:

>>> psutil.disk_partitions () # disk partition information 
[sdiskpart (Device = ' / dev / disk1 ' , the mountpoint = ' / ' , FStype = ' HFS ' , the opts = ' RW, local, the rootfs, dovolfs, Journaled, the multilabel ' )]
 >>> psutil.disk_usage ( ' / ' ) # disk usage 
sdiskusage (Total = 998 982 549 504 , used = 390 880 133 120 , = Free 607 840 272 384 , Percent = 39.1 )
 >>> psutil.disk_io_counters () # disk IO 
sdiskio (read_count = 988 513, write_count=274457, read_bytes=14856830464, write_bytes=17509420032, read_time=2228966, write_time=1618405)

It can be seen disk '/'total capacity is 998982549504 = 930 GB, using 39.1%. File format is HFS, optscontains rwexpress writable, journaledexpressed support for the logs.

Obtaining Network Information

psutil may acquire the network interface and the network connection information:

>>> psutil.net_io_counters () # of bytes read acquiring network / packet number 
snetio (bytes_sent = 3,885,744,870 , bytes_recv = 10,357,676,702 , packets_sent = 10,613,069 , packets_recv = 10,423,357 , ERRIN = 0 , ERROUT = 0 , DROPIN = 0 , = Dropout 0 )
 >>> psutil.net_if_addrs () Gets the network interface information # 
{ 
  ' lo0 ' : [SNIC (Family = <AddressFamily.AF_INET: 2 >, address = ' 127.0.0.1 ' , Netmask = ' 255.0.0.0 ' ), ...],
   ' EN1 ': [SNIC (Family = <AddressFamily.AF_INET: 2 >, address = ' 10.0.1.80 ' , Netmask = ' 255.255.255.0 ' ), ...],
   ' en0 ' : [...],
   ' EN2 ' : [...],
   ' the bridge0 ' : [...] 
}
 >>> psutil.net_if_stats () Get network Interface status # 
{ 
  ' lo0 ' : snicstats (ISUP = True, Duplex = <NicDuplex.NIC_DUPLEX_UNKNOWN: 0 >, = Speed 0 , MTU = 16384 ),
   ' en0 ': snicstats(isup=True, duplex=<NicDuplex.NIC_DUPLEX_UNKNOWN: 0>, speed=0, mtu=1500),
  'en1': snicstats(...),
  'en2': snicstats(...),
  'bridge0': snicstats(...)
}
要获取当前网络连接信息，使用net_connections()：

>>> psutil.net_connections()
Traceback (most recent call last):
  ...
PermissionError: [Errno 1] Operation not permitted

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  ...
psutil.AccessDenied: psutil.AccessDenied (pid=3847)

You might get an AccessDeniederror because psutil also go to get information system interface, network connection and get the information you need root privileges, in this case, exit the Python interactive environment, with a sudorestart:

$ sudo python3
Password: ******
Python 3.6.3 ... on darwin
Type "help", ... for more information.
>>> import psutil
>>> psutil.net_connections()
[
    sconn(fd=83, family=<AddressFamily.AF_INET6: 30>, type=1, laddr=addr(ip='::127.0.0.1', port=62911), raddr=addr(ip='::127.0.0.1', port=3306), status='ESTABLISHED', pid=3725),
    sconn(fd=84, family=<AddressFamily.AF_INET6: 30>, type=1, laddr=addr(ip='::127.0.0.1', port=62905), raddr=addr(ip='::127.0.0.1', port=3306), status='ESTABLISHED', pid=3725),
    sconn(fd=93, family=<AddressFamily.AF_INET6: 30>, type=1, laddr=addr(ip='::', port=8080), raddr=(), status='LISTEN', pid=3725),
    sconn(fd=103, family=<AddressFamily.AF_INET6: 30>, type=1, laddr=addr(ip='::127.0.0.1', port=62918), raddr=addr(ip='::127.0.0.1', port=3306), status='ESTABLISHED', pid=3725),
    sconn(fd=105, family=<AddressFamily.AF_INET6: 30>, type=1, ..., pid=3725),
    sconn(fd=106, family=<AddressFamily.AF_INET6: 30>, type=1, ..., pid=3725),
    sconn(fd=107, family=<AddressFamily.AF_INET6: 30>, type=1, ..., pid=3725),
    ...
    sconn(fd=27, family=<AddressFamily.AF_INET: 2>, type=2, ..., pid=1)
]

To get process information

You can get all the details of the process by psutil:

>>> psutil.pids () All processes # ID 
[ 1-3865 , 3864 , 3863 , 3856 , 3855 , 3853 , 3776 , ..., 45 , 44 is , . 1 , 0 ]
 >>> psutil.Process = P ( 3776 ) # = Gets the process ID 3776 , in fact, is the current Python interactive environment
 >>> p.name () # process name
 ' python3.6 ' 
>>> p.exe () # process exe path
 ' / the Users / Michael / anaconda3 / bin / python3.6 ' 
>>> p.cwd () # process working directory
 '/Users/michael' 
>>> p.cmdline () command to start the process # 
[ ' to python3 ' ]
 >>> p.ppid () # parent process ID
 3765 
>>> p.parent () # parent
 <psutil.Process (pid = 3765 , name = ' the bash ' ) AT 4503144040 > 
>>> p.children () list of sub-process # 
[]
 >>> p.status () process state #
 ' running ' 
>>> p.username () process # user name
 ' Michael ' 
>>> p.create_time () # process creation time
 1511052731.120333 
>>>p.terminal () # terminal process
 '/ dev / ttys002 ' 
>>> the CPU time p.cpu_times () # process uses 
pcputimes (User = 0.081150144 , System = .053269812 , children_user = 0.0 , children_system = 0.0 )
 >>> p.memory_info () # Process memory 
PMEM (rss = 8,310,784 , VMS = 2481725440 , pfaults = 3207 , pageins = 18 )
 >>> p.open_files () # process open file 
[]
 >>> p.connections () # processes associated Fi 
[]
 >> > the number of threads p.num_threads () # process
 1 
>>> p.threads () # all threads information 
[pthread (id= . 1 , user_time = .090318 , SYSTEM_TIME = .062736 )]
 >>> p.environ () process environment variables # 
{ ' the SHELL ' : ' / bin / the bash ' , ' the PATH ' : ' / usr / local / bin: / usr / bin: / bin: / usr / sbin: / sbin: ... ' , ' the PWD ' : ' / the Users / Michael ' , ' the LANG ' : ' zh_CN.UTF-. 8 ' , ...}
 >>> P .terminate () # end process 
Terminated:15<- own up to the end of his 
time process and obtain a network connection is similar to a root user needs to obtain root privileges, start the Python interactive environment or .py file, you need sudo privileges. 

psutil also provides a test () function, can simulate the effect of the ps command: 

$ sudo python3 
Password: ****** 
Python 3.6 . 3 ... ON darwin 
Type " Help " , ... for More Information.
 >>> Import psutil
 >>> psutil.test () 
the USER PID % MEM TTY RSS VSZ the START the TIME the COMMAND 
root            0  24.0  74,270,628  2.01638 million Nov18?    40 : 51  kernel_task
root           1  0.1 2494140    9484 ?             Nov18   01:39  launchd
root          44  0.4 2519872   36404 ?             Nov18   02:02  UserEventAgent
root          45    ? 2474032    1516 ?             Nov18   00:14  syslogd
root          47  0.1 2504768    8912 ?             Nov18   00:03  kextd
root          48   0.1  2505544     4720 ? Nov18    00 : 19   fseventsd 
appleeven     52   0.1  2499748     5024 ? Nov18    00 : 00   appleeventsd 
in to the root           , with 53   0.1  2500592     6132 ? Nov18    00 : 02   configd 
...

summary

psutil such Python program information acquiring system becomes easy.

psutil can also get a lot of useful information systems user information, Windows services, and other details, please refer psutil official website: https://github.com/giampaolo/psutil