A collection of ideas and notes about stuff to implement in future versions.

Inconsistencies

(the “too late” section)

  • PROCFS_PATH should have been set_procfs_path().

  • virtual_memory() should have been memory_virtual().

  • swap_memory() should have been memory_swap().

  • Named tuples are problematic. Positional unpacking of named tuples could be deprecated. Return frozen dataclasses (with a common base class) instead of typing.NamedTuple. The base class would keep _fields, _asdict() and len() for compat, but __iter__ and __getitem__ would emit DeprecationWarning. Main concern: isinstance(x, tuple) would break.

Rejected ideas

  • #550: threads per core
  • #1667: process_iter(new_only=True)

Features

  • #2794: enrich Process.wait() return value with exit code enums.

  • net_if_addrs() could return AF_BLUETOOTH interfaces. E.g. https://pypi.org/project/netifaces does this.

  • Use resource.getrusage() to get current process CPU times (it has more precision).

  • (UNIX) Process.root() (different from cwd()).

  • (Linux) locked files via /proc/locks: https://www.centos.org/docs/5/html/5.2/Deployment_Guide/s2-proc-locks.html

  • #269: NIC rx/tx queue. This should probably go into net_if_stats(). Figure out on what platforms this is supported. Linux: yes. Others?

  • Asynchronous psutil.Popen (see http://bugs.python.org/issue1191964)

  • (Windows) fall back on using WMIC for Process methods returning AccessDenied.

  • #613: thread names; patch for macOS available at: https://code.google.com/p/plcrashreporter/issues/detail?id=65 Sample code: https://github.com/janmojzis/pstree/blob/master/proc_kvm.c

  • scripts/taskmgr-gui.py (using tk).

  • system-wide number of open file descriptors:

  • Number of system threads.

  • psutil.proc_tree() something which obtains a {pid:ppid, ...} struct for all running processes in one shot. This can be factored out from Process.children() and exposed as a first class function. PROS: on Windows we can take advantage of ppid_map(), which is faster than iterating over all PIDs. CONS: scripts/pstree.py shows this can be easily done in the user code, so maybe it's not worth the addition.

  • advanced cmdline interface exposing the whole API and providing different kind of outputs (e.g. pprinted, colorized, json).

  • Linux: process cgroups (http://en.wikipedia.org/wiki/Cgroups). They look similar to prlimit() in terms of functionality but, uglier (they should allow limiting per-process network IO resources though, which is great). Needs further reading.

  • Python 3.3. exposed different sched.h functions: http://docs.python.org/dev/whatsnew/3.3.html#os http://bugs.python.org/issue12655 http://docs.python.org/dev/library/os.html#interface-to-the-scheduler It It might be worth to take a look and figure out whether we can include some of those in psutil.

  • os.times() provides elapsed times (Process.cpu_times() might as well?).

  • Enrich exception classes hierarchy on Python >= 3.3 / post PEP-3151 so that:

  • Process.threads() might grow an extra “id” parameter so that it can be used as:

    >>> p = psutil.Process(os.getpid())
>>> p.threads(id=psutil.current_thread_id())
thread(id=2539, user_time=0.03, system_time=0.02)
>>>

    Note: this leads to questions such as "should we have a custom NoSuchThread exception? Also see issue #418. Also note: this would work with os.getpid() only. psutil.current_thread_id() might be desirable as per issue #418 though.

  • should TimeoutExpired exception have a ‘msg’ kwarg similar to NoSuchProcess and AccessDenied? Not that we need it, but currently we cannot raise a TimeoutExpired exception with a specific error string.

  • round `Process.memory_percent() result?

Resources

System tools source code

Source code of system monitoring tools (ps, top, vmstat, etc.) on various platforms. Useful as a reference when implementing or verifying psutil's platform-specific code.

Linux

macOS

Apple open-source distributions: https://github.com/apple-oss-distributions/

FreeBSD

Repository: https://github.com/freebsd/freebsd-src

NetBSD

Repository: https://github.com/NetBSD/src

OpenBSD

Repository: https://github.com/openbsd/src

Other tools

Stats

Doc

Blog

Example sites using sphinx ablog:

Nice sites