You're reading the development version of the psutil docs, which may describe unreleased changes. For the current release see psutil.readthedocs.io/stable.

Changelog

8.0.0 (IN DEVELOPMENT)

Note

psutil 8.0 introduces breaking API changes. See the migration guide if upgrading from 7.x.

Enhancements

Doc improvements (#2761, #2757, #2760, #2745, #2763, #2764, #2767, #2768, #2769, #2771, #2774, #2775, #2781, #2787, #2739, #2790, #2797, #2801, #2803, #2808, #2819, #2820, #2823, #2826, #2828, #2829)

• Split docs from a single HTML file into multiple new sections:

  • /about (linked from footer) list all keyboard shortcuts

  • /adoption: notable software using psutil

  • /alternatives: list of alternative Python libraries and tools that overlap with psutil.

  • /api-overview: show entire API via REPL usage examples

  • /credits: list contributors and donors (was old CREDITS in root dir)

  • /faq: extended FAQ section

  • /funding: list funding methods and current sponsors

  • /genindex: a general index

  • /glossary: core concepts explained

  • /install: (was old INSTALL.rst in root dir)

  • /migration: explain how to migrate to newer psutil versions that break backward compatibility

  • /performance: how to use psutil efficiently

  • /platform: summary of OSes and architectures support

  • /recipes: code samples

  • /shell-equivalents: maps each psutil API to native CLI commands

  • /stdlib-equivalents: maps psutil’s Python API to the closest equivalent in the Python standard library

• Blog:

  • #2825: new blog at /blog, built via the ablog Sphinx extension, with 20 posts imported from https://gmpy.dev, covering psutil topics from 2014 to 2026. Includes Atom feed. Posts are searchable. Use OpenGraph for nice preview when posts are shared on social media.

• Theming:

  • Renewed, modern, custom theme.

  • Top bar

  • Toggable dark theme (Shift+D keyboard shortcut).

  • Show “last updated” and external icons in the footer.

  • Show icon for external URLs.

  • Use Monokai theme for code snippets.

• Usability:

  • Right TOC sidebar.

  • Improved overall doc clarity and shortened long sentences.

  • Show a clickable COPY button to copy code snippets.

  • Show psutil. prefix for all APIs.

  • Keyboard shortcuts:

    • ?: show helper

    • Shift + D: toggle dark/light mode.

    • Ctrl+K to focus the search box.

    • Up/Down arrow keys navigate search results; Enter opens the selected result.

  • Search results are styled as cards with subtle borders and shadows.

  • Identifiers in code blocks (e.g. psutil.Process(), p.cpu_percent()) are now clickable and link to their API reference entry on click, via sphinx-codeautolink.

  • A “back to top” button.

• Testing:

  • Replace rstcheck with sphinx-lint for RST linting.

  • Add custom script to detect dead reference links in .rst files.

  • Use sphinx extension to validate Python code snippets syntax at build-time.

  • New make test-docs with sanity checks for built HTML docs.

• Hosting:

  • Doc is no longer hosted on Read the Docs. It’s now self-hosted on GitHub Pages under a new domain: https://psutil.io. URLs no longer carry the /en language and version prefixes (e.g. https://psutil.io/faq/).

  • Doc is rebuilt and deployed automatically on every push to master.

• Misc:

  • Build doc as part of CI process (fails on error).

  • All .rst files are now wrapped to 79 characters via https://github.com/giampaolo/rstwrap.

  • Add /sitemap.xml to help search engine discovery.

  • Custom 404 page. Hovering over the © copyright in the footer reveals an easter egg. Clicking it takes you to the 404 page containing a joke.

Type hints / enums:

• #1946: Add inline type hints to all public APIs in psutil/__init__.py. Type checkers (mypy, pyright, etc.) can now statically verify code that uses psutil. No runtime behavior is changed; the annotations are purely informational.

• #2751: Convert all named tuples from collections.namedtuple() to typing.NamedTuple classes with type annotations. This makes the classes self-documenting, effectively turning this module into a readable API reference.

• #2753: Introduce enum classes (ProcessStatus, ConnectionStatus, ProcessIOPriority, ProcessPriority, ProcessRlimit) grouping related constants. The individual top-level constants (e.g. STATUS_RUNNING) remain the primary API, and are now aliases for the corresponding enum members.

New APIs:

• #2798: new Process.attrs class attribute, a frozenset of valid attribute names accepted by Process.as_dict() and process_iter(). Replaces the old pattern of calling list(psutil.Process().as_dict().keys()). Passing an empty list to process_iter() (attrs=[]) to mean “retrieve all attributes” is deprecated. Use attrs=Process.attrs instead. See migration guide.

• #1541: New Process.page_faults() method, returning a (minor, major) named tuple.

• Reorganization of process memory APIs (#2731, #2736, #2723, #2733).

  • Add new Process.memory_info_ex() method (not to be confused with the old method with the same name, deprecated in 4.0 and removed in 7.0), which extends Process.memory_info() with platform-specific metrics:

    • Linux: peak_rss, peak_vms, rss_anon, rss_file, rss_shmem, swap, hugetlb

    • macOS: peak_rss, rss_anon, rss_file, wired, compressed, phys_footprint

    • Windows: virtual, peak_virtual

  • Add new Process.memory_footprint() method, which returns uss, pss and swap metrics (what Process.memory_full_info() used to return, which is now deprecated, see migration guide).

  • Process.memory_info() named tuple changed:

    • BSD: added peak_rss.

    • Linux: lib and dirty removed (always 0 since Linux 2.6). Deprecated aliases returning 0 and emitting DeprecationWarning are kept.

    • macOS: pfaults and pageins removed with no backward-compatible aliases. Use Process.page_faults() instead.

    • Windows: eliminated old aliases: wset → rss, peak_wset → peak_rss, pagefile and private → vms, peak_pagefile → peak_vms. At the same time paged_pool, nonpaged_pool, peak_paged_pool, peak_nonpaged_pool were moved to Process.memory_info_ex(). All these old names still work but raise DeprecationWarning. See migration guide.

  • Process.memory_full_info() is deprecated. Use the new Process.memory_footprint() instead. See migration guide.

Others:

• #2687, [SunOS]: users() fails with ValueError.

• #2747: the field order of the named tuple returned by cpu_times() has been normalized on all platforms, and the first 3 fields are now always user, system, idle. See compatibility notes below.

• #2754: standardize sensors_battery()’s percent so that it returns a float instead of int on all systems, not only Linux.

• #2765: add a PR bot that uses Claude to summarize PR changes and update changelog.rst and credits.rst when commenting with /changelog.

• #2766: remove remaining Python 2.7 compatibility shims from setup.py, simplifying the build infrastructure.

• #2772, [Windows]: cpu_times() interrupt field renamed to irq to match the field name used on Linux and BSD. interrupt still works but raises DeprecationWarning. See migration guide.

• #2776, [Windows]: virtual_memory() now includes cached and wired fields.

• #2780, [Windows]: disk_usage() now can accept a file path (not only a directory path).

• #2784: process_iter(): when attrs is specified, the pre-fetched values are now cached directly on the Process instance. Subsequent method calls (e.g. p.name(), p.status()) return the cached values instead of making new system calls. The p.info dict is deprecated. See migration guide.

• #2788: git tags renamed from release-X.Y.Z to vX.Y.Z (e.g. release-7.2.2 → v7.2.2). Old tags are kept for backward compatibility.

• #2799: Process.as_dict() now returns a dict with keys sorted alphabetically when attrs is not specified.

• #2805, [BSD]: remove procfs dependency on NetBSD for cpu_stats() and virtual_memory(); values are now retrieved via the sysctl(9) and uvm(9) kernel APIs instead. (patch by Santhosh Raju)

• #2816, [OpenBSD]: swap_memory() sin and sout are no longer set to 0.

• #2844: removed docs/ from tarball. Tarball before: 586K. Tarball now: 396K.

Bug fixes

• #1007, [Windows]: boot_time() no longer fluctuates by ~1 second across calls or across processes. It is now read atomically from the kernel via NtQuerySystemInformation(SystemTimeOfDayInformation), replacing the old time.time() - uptime() computation that sampled two counters from Python and produced sub-second differences.

• #2382, [macOS]: cpu_freq() is now always defined on ARM64 and returns None when CPU frequency can’t be determined. Previously it was left undefined (or raised RuntimeError) when the pmgr IORegistry entry or its frequency data was unavailable, e.g. on virtualized ARM64 like CI runners.

• #2411 [macOS]: Process.cpu_times() and Process.cpu_percent() calculation on macOS x86_64 (arm64 is fine) was highly inaccurate (41.67x lower).

• #2642, [macOS]: fix cpu_freq() on Apple Silicon. On M4+ it returned values ~1000x too small because the voltage-statesN-sram IORegistry tables switched from Hz to kHz; on M5-family chips it failed because the hardcoded table indexes were renumbered. The implementation now enumerates CPU voltage-states*-sram tables dynamically, detects the unit per-value by magnitude, and filters CPU clusters from GPU/NPU tables via a per-table fmax threshold. Works uniformly from M1 through M5 Max. (patch by Bert Pluymers)

• #2628, [Linux]: cpu_freq() no longer takes offline CPU cores into account. They were reported with all-zero frequencies, which dragged down the average current, min and max values.

• #2711, [Windows]: net_if_addrs() was returning None for the broadcast field of network interfaces instead of the correct broadcast address.

• #2715, [Linux]: wait_pid_pidfd_open() (from Process.wait()) crashes with EINVAL due to kernel race condition.

• #2726, [macOS]: Process.num_ctx_switches() return an unusual high number due to a C type precision issue.

• #2732, [Linux]: net_if_stats(): handle EBUSY from ioctl(SIOCETHTOOL).

• #2744, [NetBSD]: fix possible double free() in swap_memory().

• #2746, [FreeBSD]: Process.memory_maps(), rss and private fields are erroneously reported in memory pages instead of bytes. Other platforms (Linux, macOS, Windows) return bytes.

• #2770, [Linux]: fix cpu_count() (logical=False) raising ValueError on s390x architecture, where /proc/cpuinfo uses spaces before the colon separator instead of a tab.

• #2778, [UNIX]: net_if_addrs() skips interfaces with no addresses, which are typically virtual IPv4/IPv6 tunnel interfaces. Now they are included in the returned dict with family == socket.AF_UNSPEC and an empty list of addresses. Main reason: it creates an inconsistency with net_io_counters() and net_if_stats() which do return these interface names.

• #2782, [FreeBSD]: cpu_count() logical=False return None on systems without hyper threading.

• #2789, [AIX]: fix compilation error caused by a typo (accidental space) in psutil_net_io_counters(), introduced during a previous code reformatting.

• #2791, [FreeBSD]: relax psutil_sysctl() / psutil_sysctlbyname() to allow the kernel to return fewer bytes than the buffer (normal for variable-length sysctl data).

• #2793: process_iter() was silently dropping zombie processes because ZombieProcess (a subclass of NoSuchProcess) was caught by the wrong except clause. Zombie processes are now yielded correctly.

• #2795, [FreeBSD]: fix cpu_freq() failing with RuntimeError: sysctlbyname('dev.cpu.0.freq_levels') size mismatch on some systems.

• #2809, [Linux]: swap_memory() and virtual_memory() raise ValueError if /proc/meminfo contains a field with no space after the colon, e.g. ShadowCallStack:10373888 kB, which occurs on arm64 when shadow call stacks exceed 10 GB.

• #2811, [OpenBSD]: virtual_memory() shared field returned pages instead of bytes, plus it was overvalued (summed shared virtual + real, now we only return real).

• #2813, [OpenBSD]: virtual_memory() buffers was always 0. Now it returns a meaningful value, which is the same as cached. That’s because OpenBSD does not distinguish between the 2.

• #2814, [NetBSD]: virtual_memory() cached is overvalued, since it includes anonymous pages.

• #2815, [OpenBSD]: virtual_memory() shared was overvalued (summed shared virtual + real, now we only return real).

• #2822, [BSD]: Process.cmdline() on NetBSD could raise OSError: [Errno 14] Bad address if the process about to exit. It now raises NoSuchProcess instead.

• #2841, [macOS]: cpu_freq() could raise SystemError when CPU frequency data is missing or invalid in the IORegistry (e.g. on Apple M5 chips). It now returns None instead (see #2382).

• #2854, [macOS]: Process.cmdline() and Process.environ() could raise SystemError after sysctl(KERN_PROCARGS2) failed with errno == 0. They now raise AccessDenied instead.

• #2857, [Linux], [SunOS]: fix refcount leak in disk_partitions() (Linux) and proc_environ() (SunOS) when PyArg_ParseTuple fails: parse arguments before allocating the result container, matching the pattern used in the other 26 call sites. Also fix a copy-paste typo in SunOS proc_environ() where the post-decode NULL check examined the wrong variable (py_envname instead of py_envval), which could let a NULL value reach PyDict_SetItem.

• #2859, [Windows]: net_connections() / Process.net_connections() could crash with an invalid Py_DECREF(NULL) when argument parsing failed before the result list was allocated. The error path now uses Py_XDECREF (including the temporary address-family / socket-type objects).

• #2860, [Linux]: Process.cpu_affinity() could crash the interpreter with a segfault when PyLong_FromLong() returned NULL under memory pressure; the NULL is now checked and a proper MemoryError is raised instead.

• #2871, [Linux]: Process.rlimit() returned RLIM_INFINITY as the unsigned 2**64-1 instead of -1 on Python 3.15+, which changed resource.prlimit() accordingly. psutil now maps it back to psutil.RLIM_INFINITY so the value stays consistent across Python versions.

7.2.2 — 2026-01-28

Enhancements

• #2705: [Linux]: Process.wait() now uses pidfd_open() + poll() (no busy loop). Requires Linux >= 5.3 and Python >= 3.9.

• #2705: [macOS], [BSD]: Process.wait() now uses kqueue() (no busy loop).

Bug fixes

• #2701, [macOS]: fix compilation error on macOS < 10.7. (patch by Sergey Fedorov)

• #2707, [macOS]: fix potential memory leaks in error paths of Process.memory_full_info() and Process.threads().

• #2708, [macOS]: Process.cmdline() and Process.environ() may fail with OSError: [Errno 0] Undefined error (from sysctl(KERN_PROCARGS2)). They now raise AccessDenied instead.

7.2.1 — 2025-12-29

Bug fixes

• #2699, [FreeBSD], [NetBSD]: heap_info() does not detect small allocations (<= 1K). In order to fix that, we now flush internal jemalloc cache before fetching the metrics.

7.2.0 — 2025-12-23

Enhancements

• #1275: new heap_info() and heap_trim() functions, providing direct access to the platform’s native C heap allocator (glibc, mimalloc, libmalloc). Useful to create tools to detect memory leaks.

• #2403, [Linux]: publish wheels for Linux musl.

• #2680: unit tests are no longer installed / part of the distribution. They now live under tests/ instead of psutil/tests.

Bug fixes

• #2684, [FreeBSD], [critical]: compilation fails on FreeBSD 14 due to missing include.

• #2691, [Windows]: fix memory leak in net_if_stats() due to missing Py_CLEAR.

Compatibility notes

• #2680: import psutil.tests no longer works (but it was never documented to begin with).

7.1.3 — 2025-11-02

Enhancements

• #2667: enforce clang-format on all C and header files. It is now the mandatory formatting style for all C sources.

• #2672, [macOS], [BSD]: increase the chances to recognize zombie processes and raise the appropriate exception (ZombieProcess).

• #2676, #2678: replace unsafe sprintf / snprintf / sprintf_s with str_format, and strlcat / strlcpy with str_copy / str_append. Unifies string handling across platforms.

Bug fixes

• #2674, [Windows]: disk_usage() could truncate values on 32-bit platforms, potentially reporting incorrect total, free, used space for drives larger than 4GB.

• #2675, [macOS]: Process.status() incorrectly returns STATUS_RUNNING for 99% of the processes.

• #2677, [Windows]: fix MAC address string construction in net_if_addrs() (buffer overflow / misformat risk).

• #2679, [OpenBSD], [NetBSD], [critical]: can’t build due to C syntax error.

7.1.2 — 2025-10-25

Enhancements

• #2657: stop publishing prebuilt Linux and Windows wheels for 32-bit Python. 32-bit CPython is still supported, but psutil must now be built from source. #2565: produce wheels for free-thread cPython 3.13 and 3.14 (patch by Lysandros Nikolaou)

Bug fixes

• #2650, [macOS]: Process.cmdline() and Process.environ() may incorrectly raise NoSuchProcess instead of ZombieProcess.

• #2658, [macOS]: double free() in Process.environ() when it fails internally. This posed a risk of segfault.

• #2662, [macOS]: massive C code cleanup to guard against possible segfaults which were (not so) sporadically spotted on CI.

Compatibility notes

• #2657: stop publishing prebuilt Linux and Windows wheels for 32-bit Python.

7.1.1 — 2025-10-19

Enhancements

• #2645, [SunOS]: dropped support for SunOS 10.

• #2646, [SunOS]: add CI test runner for SunOS.

Bug fixes

• #2641, [SunOS]: cannot compile psutil from sources due to missing C include.

• #2357, [SunOS]: Process.cmdline() does not handle spaces properly. (patch by Ben Raz)

Compatibility notes

• #2645: SunOS 10 is no longer supported.

7.1.0 — 2025-09-17

Enhancements

• #2581, [Windows]: publish ARM64 wheels. (patch by Matthieu Darbois)

• #2571, [FreeBSD]: Dropped support for FreeBSD 8 and earlier. FreeBSD 8 was maintained from 2009 to 2013.

• #2575: introduced dprint CLI tool to format .yml and .md files.

Bug fixes

• #2473, [macOS]: Fix build issue on macOS 11 and lower.

• #2494, [Windows]: Process.memory_maps(), Process.exe() and Process.open_files() now properly handle UNC paths (e.g. \\??\\C:\\Windows\\Temp → C:\\Windows\\Temp). (patch by Ben Peddell)

• #2506, [Windows]: Windows service APIs had issues with unicode services using special characters in their name.

• #2514, [Linux]: Process.cwd() sometimes fail with FileNotFoundError due to a race condition.

• #2526, [Linux]: Process.create_time() now uses a monotonic clock, preventing Process.is_running() from returning wrong results after system clock updates. (patch by Jonathan Kohler)

• #2528, [Linux]: Process.children() may raise PermissionError. It will now raise AccessDenied instead.

• #2540, [macOS]: boot_time() is off by 45 seconds (C precision issue).

• #2541, #2570, #2578 [Linux], [macOS], [NetBSD]: Process.create_time() does not reflect system clock updates.

• #2542: if system clock is updated Process.children() and Process.parent() may not be able to return the right information.

• #2545: [Illumos]: Fix handling of MIB2_UDP_ENTRY in net_connections().

• #2552, [Windows]: boot_time() didn’t take into account the time spent during suspend / hibernation.

• #2560, [Linux]: Process.memory_maps() may crash with IndexError on RISCV64 due to a malformed /proc/pid/smaps file. (patch by Julien Stephan)

• #2586, [macOS], [CRITICAL]: fixed different places in C code which can trigger a segfault.

• #2604, [Linux]: virtual_memory() used field does not match recent versions of free CLI utility. (patch by Isaac K. Ko)

• #2605, [Linux]: sensors_battery() reports a negative amount for seconds left.

• #2607, [Windows]: WindowsService.description() method may fail with ERROR_NOT_FOUND. Now it returns an empty string instead.

• 2610:, [macOS], [CRITICAL]: fix cpu_freq() segfault on ARM architectures.

Compatibility notes

• #2571: dropped support for FreeBSD 8 and earlier.

7.0.0 — 2025-02-13

Enhancements

• #669, [Windows]: net_if_addrs() also returns the broadcast address instead of None.

• #2480: drop Python 2.7 support. Latest version supporting it is psutil 6.1.X (pip2 install psutil==6.1.*).

• #2490: remove long deprecated Process.memory_info_ex() (deprecated since 4.0.0). Use Process.memory_full_info() instead.

Bug fixes

• #2496, [Linux]: Avoid segfault (a cPython bug) on Process.memory_maps() for processes that use hundreds of GBs of memory.

• #2502, [macOS]: virtual_memory() now uses host_statistics64 (same as vm_stat), more accurate.

Compatibility notes

• #2480: Python 2.7 is no longer supported.

• #2490: removed long deprecated Process.memory_info_ex() method.

6.1.1 — 2024-12-19

Enhancements

• #2471: use Vulture CLI tool to detect dead code.

Bug fixes

• #2418, [Linux]: fix race condition in case /proc/pid/stat does not exist, but /proc/pid does, resulting in FileNotFoundError.

• #2470, [Linux]: users() may return “localhost” instead of the actual IP address of the user logged in.

6.1.0 — 2024-10-17

Enhancements

• #2366, [Windows]: drastically speedup process_iter() by using process “fast” create time to determine process identity.

• #2446: use pytest instead of unittest.

• #2448: add make install-sysdeps target to install the necessary system dependencies (python-dev, gcc, etc.) on all supported UNIX flavors.

• #2449: add make install-pydeps-test and make install-pydeps-dev targets. They can be used to install dependencies meant for running tests and for local development. They can also be installed via pip install .[test] and pip install .[dev].

• #2456: allow running tests via python3 -m psutil.tests even if pytest is not installed.

Bug fixes

• #2427: psutil (segfault) on import in the free-threaded (no GIL) version of Python 3.13. (patch by Sam Gross)

• #2455, [Linux]: IndexError may occur when reading /proc/pid/stat and field 40 (blkio_ticks) is missing.

• #2457, [AIX]: significantly improve the speed of Process.open_files() for some edge cases.

• #2460, [OpenBSD]: Process.num_fds() and Process.open_files() may fail with NoSuchProcess for PID 0. Instead, we now return “null” values (0 and [] respectively).

6.0.0 — 2024-06-18

Enhancements

• #2109: remove maxfile and maxpath from disk_partitions() (can be very slow on NFS).

• #2366, [Windows]: log debug message when using slower process APIs.

• #2375, [macOS]: provide arm64 wheels. (patch by Matthieu Darbois)

• #2396: process_iter() no longer preemptively checks whether PIDs have been reused, making it around 20x faster.

• #2396: a new process_iter.cache_clear() API can be used to clear process_iter() internal cache.

• #2401, Support building with free-threaded CPython 3.13. (patch by Sam Gross)

• #2407: rename Process.connections() to Process.net_connections(). Old name still works but is deprecated.

• #2425: [Linux]: provide aarch64 wheels. (patch by Matthieu Darbois / Ben Raz)

Bug fixes

• #2250, [NetBSD]: Process.cmdline() sometimes fail with EBUSY for long cmdlines. Now retries up to 50 times, returning an empty list as last resort.

• #2254, [Linux]: offline cpus raise NotImplementedError in cpu_freq() (patch by Shade Gladden)

• #2272: Add pickle support to psutil Exceptions.

• #2359, [Windows], [CRITICAL]: pid_exists() disagrees with Process on whether a pid exists when ERROR_ACCESS_DENIED.

• #2360, [macOS]: can’t compile on macOS < 10.13. (patch by Ryan Schmidt)

• #2362, [macOS]: can’t compile on macOS 10.11. (patch by Ryan Schmidt)

• #2365, [macOS]: can’t compile on macOS < 10.9. (patch by Ryan Schmidt)

• #2395, [OpenBSD]: pid_exists() erroneously return True if the argument is a thread ID (TID) instead of a PID (process ID).

• #2412, [macOS]: can’t compile on macOS 10.4 PowerPC due to missing MNT_ constants.

Porting notes

Version 6.0.0 introduces some changes which affect backward compatibility:

• #2109: the named tuple returned by disk_partitions()’ no longer has maxfile and maxpath fields.

• #2396: process_iter() no longer preemptively checks whether PIDs have been reused. Use Process.is_running() on yielded instances instead (also removes reused PIDs from the internal cache).

• #2407: rename Process.connections() to Process.net_connections(). Old name still works but is deprecated.

5.9.8 — 2024-01-19

Enhancements

• #2343, [FreeBSD]: filter net_connections() in C instead of Python, ~4x faster. Only requested connection types are now retrieved.

• #2342, [NetBSD]: same as above (#2343) but for NetBSD.

• #2349: adopted black formatting style.

Bug fixes

• #930, [NetBSD], [critical]: net_connections() implementation was broken. It could either leak memory or core dump.

• #2340, [NetBSD]: if process is terminated, Process.cwd() will return an empty string instead of raising NoSuchProcess.

• #2345, [Linux]: fix compilation on older compiler missing NIC_DUPLEX_UNKNOWN.

• #2222, [macOS]: cpu_freq() now returns fixed values for min and max frequencies in all Apple Silicon chips.

5.9.7 — 2023-12-17

Enhancements

• #2324: enforce Ruff rule raw-string-in-exception, which helps providing clearer tracebacks when exceptions are raised by psutil.

Bug fixes

• #2325, [PyPy]: psutil did not compile on PyPy due to missing PyErr_SetExcFromWindowsErrWithFilenameObject cPython API.

5.9.6 — 2023-10-15

Enhancements

• #1703: cpu_percent() and cpu_times_percent() are now thread safe.

• #2266: if Process class is passed a very high PID, raise NoSuchProcess instead of OverflowError. (patch by Xuehai Pan)

• #2246: drop python 3.4 & 3.5 support. (patch by Matthieu Darbois)

• #2290: PID reuse is now preemptively checked for Process.ppid() and Process.parents().

• #2312: use ruff linter instead of flake8 + isort.

Bug fixes

• #2195, [Linux]: no longer print exception at import time in case /proc/stat can’t be read due to permission error. Redirect it to PSUTIL_DEBUG instead.

• #2241, [NetBSD]: can’t compile On NetBSD 10.99.3/amd64. (patch by Thomas Klausner)

• #2245, [Windows]: fix var unbound error on possibly in swap_memory() (patch by student_2333)

• #2268: bytes2human() utility function was unable to properly represent negative values.

• #2252, [Windows]: disk_usage() fails on Python 3.12+. (patch by Matthieu Darbois)

• #2284, [Linux]: Process.memory_full_info() may incorrectly raise ZombieProcess if it’s determined via /proc/pid/smaps_rollup. Instead we now fallback on reading /proc/pid/smaps.

• #2287, [OpenBSD], [NetBSD]: Process.is_running() erroneously return False for zombie processes, because creation time cannot be determined.

• #2288, [Linux]: correctly raise ZombieProcess on Process.exe(), Process.cmdline() and Process.memory_maps() instead of returning a “null” value.

• #2290: differently from what stated in the doc, PID reuse is not preemptively checked for Process.nice() (set), Process.ionice(), (set), Process.cpu_affinity() (set), Process.rlimit() (set), Process.parent().

• #2308, [OpenBSD]: Process.threads() always fail with AccessDenied (also as root).

5.9.5 — 2023-04-17

Enhancements

• #2196: in case of exception, display a cleaner error traceback by hiding the KeyError bit deriving from a missed cache hit.

• #2217: print the full traceback when a DeprecationWarning or UserWarning is raised.

• #2230, [OpenBSD]: net_connections() rewritten from scratch: now retrieves socket.AF_UNIX socket paths, is faster, and no longer produces duplicates.

• #2238: Process.cwd() now consistently returns "" on all platforms when the directory can’t be determined.

• #2239, [UNIX]: for zombie processes, return the truncated Process.name() (15 chars) instead of raising ZombieProcess when the full name can’t be determined from Process.cmdline().

• #2240, [NetBSD], [OpenBSD]: add CI testing on every commit for NetBSD and OpenBSD platforms (python 3 only).

Bug fixes

• #1043, [OpenBSD] net_connections() returns duplicate entries.

• #1915, [Linux]: on certain kernels, "MemAvailable" field from /proc/meminfo returns 0 (possibly a kernel bug), in which case we calculate an approximation for available memory which matches “free” CLI utility.

• #2164, [Linux]: compilation fails on kernels < 2.6.27 (e.g. CentOS 5).

• #2186, [FreeBSD]: compilation fails with Clang 15. (patch by Po-Chuan Hsieh)

• #2191, [Linux]: disk_partitions(): do not unnecessarily read /proc/filesystems and raise AccessDenied unless user specified all=False argument.

• #2216, [Windows]: fix tests when running in a virtual environment (patch by Matthieu Darbois)

• #2225, [POSIX]: users() loses precision for started field (off by 1 minute).

• #2229, [OpenBSD]: unable to properly recognize zombie processes. NoSuchProcess may be raised instead of ZombieProcess.

• #2231, [NetBSD]: available virtual_memory() is higher than total.

• #2234, [NetBSD]: virtual_memory() metrics are wrong: available and used are too high. We now match values shown by htop CLI utility.

• #2236, [NetBSD]: Process.num_threads() and Process.threads() return threads that are already terminated.

• #2237, [OpenBSD], [NetBSD]: Process.cwd() may raise FileNotFoundError if cwd no longer exists. Return an empty string instead.

5.9.4 — 2022-11-07

Enhancements

• #2102: use Limited API when building wheels with CPython 3.6+ on Linux, macOS and Windows. (patch by Matthieu Darbois)

Bug fixes

• #2077, [Windows]: Use system-level values for virtual_memory(). (patch by Daniel Widdis)

• #2156, [Linux]: compilation may fail on very old gcc compilers due to missing SPEED_UNKNOWN definition. (patch by Amir Rossert)

• #2010, [macOS]: on MacOS, arm64 IFM_1000_TX and IFM_1000_T are the same value, causing a build failure. (patch by Lawrence D’Anna)

• #2160, [Windows]: get swap_memory() percent usage from performance counters. (patch by Daniel Widdis)

5.9.3 — 2022-10-18

Enhancements

• #2040, [macOS]: provide wheels for arm64 architecture. (patch by Matthieu Darbois)

Bug fixes

• #2116, [macOS], [critical]: net_connections() fails with RuntimeError.

• #2135, [macOS]: Process.environ() may contain garbage data. Fix out-of-bounds read around sysctl_procargs. (patch by Bernhard Urban-Forster)

• #2138, [Linux], [critical]: can’t compile psutil on Android due to undefined ethtool_cmd_speed symbol.

• #2142, [POSIX]: net_if_stats() ‘s flags on Python 2 returned unicode instead of str. (patch by Matthieu Darbois)

• #2147, [macOS] Fix disk usage report on macOS 12+. (patch by Matthieu Darbois)

• #2150, [Linux] Process.threads() may raise NoSuchProcess. Fix race condition. (patch by Daniel Li)

• #2153, [macOS] Fix race condition in test_posix.TestProcess.test_cmdline. (patch by Matthieu Darbois)

5.9.2 — 2022-09-04

Bug fixes

• #2093, [FreeBSD], [critical]: pids() may fail with ENOMEM. Dynamically increase the malloc() buffer size until it’s big enough.

• #2095, [Linux]: net_if_stats() returns incorrect interface speed for 100GbE network cards.

• #2113, [FreeBSD], [critical]: virtual_memory() may raise ENOMEM due to missing #include <sys/param.h> directive. (patch by Peter Jeremy)

• #2128, [NetBSD]: swap_memory() was miscalculated. (patch by Thomas Klausner)

5.9.1 — 2022-05-20

Enhancements

• #1053: drop Python 2.6 support. (patches by Matthieu Darbois and Hugo van Kemenade)

• #2037: add flags field to net_if_stats().

• #2050, [Linux]: increase read(2) buffer size from 1k to 32k when reading /proc pseudo files line by line.

• #2057, [OpenBSD]: add support for cpu_freq().

• #2107, [Linux]: Process.memory_full_info() now reads /proc/pid/smaps_rollup instead of /proc/pid/smaps (5x faster).

Bug fixes

• #2048: AttributeError is raised if psutil.Error class is raised manually and passed through str.

• #2049, [Linux]: cpu_freq() erroneously returns current value in GHz while min and max are in MHz.

• #2050, [Linux]: virtual_memory() may raise ValueError if running in a LCX container.

5.9.0 — 2021-12-29

Enhancements

• #1851, [Linux]: cpu_freq() reads from /proc/cpuinfo instead of many files in /sys fs, faster on systems with many CPUs. (patch by marxin)

• #1992: NoSuchProcess message now specifies if the PID has been reused. Error classes now have improved __repr__ and __str__.

• #1996, [BSD]: add support for MidnightBSD. (patch by Saeed Rasooli)

• #1999, [Linux]: disk_partitions(): convert /dev/root device (an alias used on some Linux distros) to real root device path.

• #2005: PSUTIL_DEBUG mode now prints file name and line number of the debug messages coming from C extension modules.

• #2042: rewrite HISTORY.rst to use hyperlinks pointing to psutil API doc.

Bug fixes

• #1456, [macOS], [critical]: cpu_freq() min and max are set to 0 if can’t be determined (instead of crashing).

• #1512, [macOS]: sometimes Process.connections() will crash with EOPNOTSUPP for one connection; this is now ignored.

• #1598, [Windows]: disk_partitions() only returns mount points on drives where it first finds one.

• #1874, [SunOS]: swap output error due to incorrect range.

• #1892, [macOS]: cpu_freq() broken on Apple M1.

• #1901, [macOS]: Process.open_files(), Process.connections() and others could randomly raise AccessDenied because the internal buffer of proc_pidinfo(PROC_PIDLISTFDS) was too small. Now dynamically increased until sufficient.

• #1904, [Windows]: OpenProcess fails with ERROR_SUCCESS due to GetLastError() called after sprintf(). (patch by @alxchk)

• #1913, [Linux]: wait_procs() should catch subprocess.TimeoutExpired exception.

• #1919, [Linux]: sensors_battery() can raise TypeError on PureOS.

• #1921, [Windows]: swap_memory() shows committed memory instead of swap.

• #1940, [Linux]: psutil does not handle ENAMETOOLONG when accessing process file descriptors in procfs. (patch by Nikita Radchenko)

• #1948, [critical]: memoize_when_activated decorator is not thread-safe. (patch by Xuehai Pan)

• #1953, [Windows], [critical]: disk_partitions() crashes due to insufficient buffer len. (patch by MaWe2019)

• #1965, [Windows], [critical]: fix “Fatal Python error: deallocating None” when calling users() multiple times.

• #1980, [Windows]: 32bit / WoW64 processes fails to read Process.name() longer than 128 characters. (patch by PetrPospisil)

• #1991, [critical]: process_iter() is not thread safe and can raise TypeError if invoked from multiple threads.

• #1956, [macOS]: Process.cpu_times() reports incorrect timings on M1 machines. (patch by Olivier Dormond)

• #2023, [Linux]: cpu_freq() return order is wrong on systems with more than 9 CPUs.

5.8.0 — 2020-12-19

Enhancements

• #1863: disk_partitions() exposes 2 extra fields: maxfile and maxpath, which are the maximum file name and path name length.

• #1872, [Windows]: added support for PyPy 2.7.

• #1879: provide pre-compiled wheels for Linux and macOS (yey!).

• #1880: switch CI from Travis/Cirrus to GitHub Actions (Linux, macOS, FreeBSD). AppVeyor still used for Windows.

Bug fixes

• #1708, [Linux]: get rid of sensors_temperatures() duplicates. (patch by Tim Schlueter).

• #1839, [Windows], [critical]: always raise AccessDenied instead of WindowsError when failing to query 64 processes from 32 bit ones by using NtWoW64 APIs.

• #1866, [Windows], [critical]: Process.exe(), Process.cmdline(), Process.environ() may raise “[WinError 998] Invalid access to memory location” on Python 3.9 / VS 2019.

• #1874, [SunOS]: wrong swap output given when encrypted column is present.

• #1875, [Windows], [critical]: Process.username() may raise ERROR_NONE_MAPPED if the SID has no corresponding account name. In this case AccessDenied is now raised.

• #1886, [macOS]: EIO error may be raised on Process.cmdline() and Process.environ(). Now it gets translated into AccessDenied.

• #1887, [Windows], [critical]: OpenProcess may fail with “[WinError 0] The operation completed successfully”.” Turn it into AccessDenied or NoSuchProcess depending on whether the PID is alive.

• #1891, [macOS]: get rid of deprecated getpagesize().

5.7.3 — 2020-10-23

Enhancements

• #809, [FreeBSD]: add support for Process.rlimit().

• #893, [BSD]: add support for Process.environ() (patch by Armin Gruner)

• #1830, [POSIX]: net_if_stats() isup also checks whether the NIC is running (meaning Wi-Fi or ethernet cable is connected). (patch by Chris Burger)

• #1837, [Linux]: improved battery detection and charge secsleft calculation (patch by @aristocratos)

Bug fixes

• #1620, [Linux]: cpu_count() with logical=False result is incorrect on systems with more than one CPU socket. (patch by Vincent A. Arcila)

• #1738, [macOS]: Process.exe() may raise FileNotFoundError if process is still alive but the exe file which launched it got deleted.

• #1791, [macOS]: fix missing include for getpagesize().

• #1823, [Windows], [critical]: Process.open_files() may cause a segfault due to a NULL pointer.

• #1838, [Linux]: sensors_battery(): if percent can be determined but not the remaining values, still return a result instead of None. (patch by @aristocratos)

5.7.2 — 2020-07-15

Bug fixes

• wheels for 2.7 were inadvertently deleted.

5.7.1 — 2020-07-15

Enhancements

• #1729: parallel tests on POSIX (make test-parallel). They’re twice as fast!

• #1741, [POSIX]: make build now runs in parallel on Python >= 3.6 and it’s about 15% faster.

• #1747: Process.wait() return value is cached so that the exit code can be retrieved on then next call.

• #1747, [POSIX]: Process.wait() on POSIX now returns an enum, showing the negative signal which was used to terminate the process. It returns something like <Negsignal.SIGTERM: -15>.

• #1747: Process class provides more info about the process on str() and repr() (status and exit code).

• #1757: memory leak tests are now stable.

• #1768, [Windows]: added support for Windows Nano Server. (contributed by Julien Lebot)

Bug fixes

• #1726, [Linux]: cpu_freq() parsing should use spaces instead of tabs on ia64. (patch by Michał Górny)

• #1760, [Linux]: Process.rlimit() does not handle long long type properly.

• #1766, [macOS]: NoSuchProcess may be raised instead of ZombieProcess.

• #1781, [critical]: getloadavg() can crash the Python interpreter. (patch by Ammar Askar)

5.7.0 — 2020-02-18

Enhancements

• #1637, [SunOS]: add partial support for old SunOS 5.10 Update 0 to 3.

• #1648, [Linux]: sensors_temperatures() looks into an additional /sys/device/ directory for additional data. (patch by Javad Karabi)

• #1652, [Windows]: dropped support for Windows XP and Windows Server 2003. Minimum supported Windows version now is Windows Vista.

• #1671, [FreeBSD]: add CI testing/service for FreeBSD (Cirrus CI).

• #1677, [Windows]: Process.exe() will succeed for all process PIDs (instead of raising AccessDenied).

• #1679, [Windows]: net_connections() and Process.connections() are 10% faster.

• #1682, [PyPy]: added CI / test integration for PyPy via Travis.

• #1686, [Windows]: added support for PyPy on Windows.

• #1693, [Windows]: boot_time(), Process.create_time() and users()’s login time now have 1 micro second precision (before the precision was of 1 second).

Bug fixes

• #1538, [NetBSD]: Process.cwd() may return ENOENT instead of NoSuchProcess.

• #1627, [Linux]: Process.memory_maps() can raise KeyError.

• #1642, [SunOS]: querying basic info for PID 0 results in FileNotFoundError.

• #1646, [FreeBSD], [critical]: many Process methods may cause a segfault due to a backward incompatible change in a C type on FreeBSD 12.0.

• #1656, [Windows]: Process.memory_full_info() raises AccessDenied even for the current user and os.getpid().

• #1660, [Windows]: Process.open_files() rewritten with proper error handling.

• #1662, [Windows], [critical]: Process.exe() may raise “[WinError 0] The operation completed successfully”.

• #1665, [Linux]: disk_io_counters() does not take into account extra fields added to recent kernels. (patch by Mike Hommey)

• #1672: use the right C type when dealing with PIDs (int or long).

• #1673, [OpenBSD]: Process.connections(), Process.num_fds() and Process.threads() raised wrong exception if process is gone.

• #1674, [SunOS]: disk_partitions() may raise OSError.

• #1684, [Linux]: disk_io_counters() may raise ValueError on systems not having /proc/diskstats.

• #1695, [Linux]: could not compile on kernels <= 2.6.13 due to PSUTIL_HAS_IOPRIO not being defined. (patch by Anselm Kruis)

5.6.7 — 2019-11-26

Bug fixes

• #1630, [Windows], [critical]: can’t compile source distribution due to C syntax error.

5.6.6 — 2019-11-25

Bug fixes

• #1179, [Linux]: Process.cmdline() now handles processes that use inappropriate chars to separate args.

• #1616, [critical]: use of Py_DECREF instead of Py_CLEAR will result in double free() and segfault (CVE-2019-18874). (patch by Riccardo Schirone)

• #1619, [OpenBSD], [critical]: compilation fails due to C syntax error. (patch by Nathan Houghton)

5.6.5 — 2019-11-06

Bug fixes

• #1615: remove pyproject.toml as it was causing installation issues.

5.6.4 — 2019-11-04

Enhancements

• #1527, [Linux]: added Process.cpu_times() iowait counter, which is the time spent waiting for blocking I/O to complete.

• #1565: add PEP 517/8 build backend and requirements specification for better pip integration. (patch by Bernát Gábor)

Bug fixes

• #875, [Windows], [critical]: Process.cmdline(), Process.environ() or Process.cwd() may occasionally fail with ERROR_PARTIAL_COPY which now gets translated to AccessDenied.

• #1126, [Linux], [critical]: Process.cpu_affinity() segfaults on CentOS 5 / manylinux. Process.cpu_affinity() support for CentOS 5 was removed.

• #1528, [AIX], [critical]: compilation error on AIX 7.2 due to 32 vs 64 bit differences. (patch by Arnon Yaari)

• #1535: type and family fields returned by net_connections() are not always turned into enums.

• #1536, [NetBSD]: Process.cmdline() erroneously raise ZombieProcess error if cmdline has non encodable chars.

• #1546: usage percent may be rounded to 0 on Python 2.

• #1552, [Windows]: getloadavg() math for calculating 5 and 15 mins values is incorrect.

• #1568, [Linux]: use CC compiler env var if defined.

• #1570, [Windows]: NtWow64* syscalls fail to raise the proper error code

• #1585, [OSX]: avoid calling close() (in C) on possible negative integers. (patch by Athos Ribeiro)

• #1606, [SunOS], [critical]: compilation fails on SunOS 5.10. (patch by vser1)

5.6.3 — 2019-06-11

Enhancements

• #1494, [AIX]: added support for Process.environ(). (patch by Arnon Yaari)

Bug fixes

• #1276, [AIX]: can’t get whole Process.cmdline(). (patch by Arnon Yaari)

• #1501, [Windows]: Process.cmdline() and Process.exe() raise unhandled “WinError 1168 element not found” exceptions for “Registry” and “Memory Compression” pseudo processes on Windows 10.

• #1526, [NetBSD], [critical]: Process.cmdline() could raise MemoryError. (patch by Kamil Rytarowski)

5.6.2 — 2019-04-26

Enhancements

• #604, [Windows]: add new getloadavg(), returning system load average calculation, including on Windows (emulated). (patch by Ammar Askar)

• #1404, [Linux]: cpu_count() with logical=False falls back to reading /sys/devices/system/cpu/*/topology/core_id if /proc/cpuinfo doesn’t provide the info.

• #1458: provide coloured test output. Also show failures on KeyboardInterrupt.

• #1464: various docfixes (always point to Python 3 doc, fix links, etc.).

• #1476, [Windows]: Process.ionice() can now set high I/O priority. New constants: IOPRIO_VERYLOW, IOPRIO_LOW, IOPRIO_NORMAL, IOPRIO_HIGH.

• #1478: add make command to re-run tests failed on last run.

Bug fixes

• #1223, [Windows]: boot_time() may return incorrect value on Windows XP.

• #1456, [Linux]: cpu_freq() returns None instead of 0.0 when min and max fields can’t be determined. (patch by Alex Manuskin)

• #1462, [Linux]: (tests) make tests invariant to LANG setting (patch by Benjamin Drung)

• #1463: scripts/cpu_distribution.py was broken.

• #1470, [Linux]: disk_partitions(): fix corner case when /etc/mtab doesn’t exist. (patch by Cedric Lamoriniere)

• #1471, [SunOS]: Process.name() and Process.cmdline() can return SystemError. (patch by Daniel Beer)

• #1472, [Linux]: cpu_freq() does not return all CPUs on Raspberry-pi 3.

• #1474: fix formatting of psutil.tests() which mimics ps aux output.

• #1475, [Windows], [critical]: OSError.winerror attribute wasn’t properly checked resulting in WindowsError(ERROR_ACCESS_DENIED) being raised instead of AccessDenied.

• #1477, [Windows]: wrong or absent error handling for private NTSTATUS Windows APIs. Different process methods were affected by this.

• #1480, [Windows], [critical]: cpu_count() with logical=False could cause a crash due to fixed read violation. (patch by Samer Masterson)

• #1486, [AIX], [SunOS]: AttributeError when interacting with Process methods involved into Process.oneshot() context.

• #1491, [SunOS]: net_if_addrs(): use free() against ifap struct on error. (patch by Agnewee)

• #1493, [Linux]: cpu_freq(): handle the case where /sys/devices/system/cpu/cpufreq/ exists but it’s empty.

5.6.1 — 2019-03-11

Bug fixes

• #1329, [AIX]: psutil doesn’t compile on AIX 6.1. (patch by Arnon Yaari)

• #1448, [Windows], [critical]: crash on import due to rtlIpv6AddressToStringA not available on Wine.

• #1451, [Windows], [critical]: Process.memory_full_info() segfaults. NtQueryVirtualMemory is now used instead of QueryWorkingSet to calculate USS memory.

5.6.0 — 2019-03-05

Enhancements

• #1379, [Windows]: Process.suspend() and Process.resume() now use NtSuspendProcess / NtResumeProcess instead of stopping / resuming all threads. Faster and more reliable.

• #1420, [Windows]: in case of exception disk_usage() now also shows the path name.

• #1422, [Windows]: DLL-loaded Windows APIs are now loaded once on startup instead of per function call, significantly faster.

• #1426, [Windows]: PAGESIZE and number of processors is now calculated on startup.

• #1428: in case of error, the traceback message now shows the underlying C function called which failed.

• #1433: new Process.parents() method. (idea by Ghislain Le Meur)

• #1437: pids() are returned in sorted order.

• #1442: Python 3 is now the default interpreter used by Makefile.

Bug fixes

• #1353: process_iter() is now thread safe (it rarely raised TypeError).

• #1394, [Windows], [critical]: Process.name() and Process.exe() may erroneously return “Registry” or fail with “[Error 0] The operation completed successfully”. QueryFullProcessImageNameW is now used instead of GetProcessImageFileNameW in order to prevent that.

• #1411, [BSD]: lack of Py_DECREF could cause segmentation fault on process instantiation.

• #1419, [Windows]: Process.environ() raises NotImplementedError when querying a 64-bit process in 32-bit-WoW mode. Now it raises AccessDenied.

• #1427, [OSX]: Process.cmdline() and Process.environ() may erroneously raise OSError on failed malloc().

• #1429, [Windows]: SE DEBUG was not properly set for current process. It is now, and it should result in less AccessDenied exceptions for low PID processes.

• #1432, [Windows]: Process.memory_info_ex()’s USS memory is miscalculated because we’re not using the actual system PAGESIZE.

• #1439, [NetBSD]: Process.connections() may return incomplete results if using Process.oneshot().

• #1447: original exception wasn’t turned into NoSuchProcess / AccessDenied exceptions when using Process.oneshot() context manager.

Incompatible API changes

• #1291, [OSX], [critical]: Process.memory_maps() was removed because inherently broken (segfault) for years.

5.5.1 — 2019-02-15

Enhancements

• #1348, [Windows]: on Windows >= 8.1, Process.cmdline() falls back to NtQueryInformationProcess on ERROR_ACCESS_DENIED. (patch by EccoTheFlintstone)

Bug fixes

• #1394, [Windows]: Process.exe() returns “[Error 0] The operation completed successfully” when Python process runs in “Virtual Secure Mode”.

• #1402: psutil exceptions’ repr() show the internal private module path.

• #1408, [AIX], [critical]: psutil won’t compile on AIX 7.1 due to missing header. (patch by Arnon Yaari)

5.5.0 — 2019-01-23

Enhancements

• #1350, [FreeBSD]: added support for sensors_temperatures(). (patch by Alex Manuskin)

• #1352, [FreeBSD]: added support for cpu_freq(). (patch by Alex Manuskin)

Bug fixes

• #1111: Process.oneshot() is now thread safe.

• #1354, [Linux]: disk_io_counters() fails on Linux kernel 4.18+.

• #1357, [Linux]: Process.memory_maps() and Process.io_counters() methods are no longer exposed if not supported by the kernel.

• #1368, [Windows]: fix Process.ionice() mismatch. (patch by EccoTheFlintstone)

• #1370, [Windows]: improper usage of CloseHandle() may lead to override the original error code when raising an exception.

• #1373, [critical]: incorrect handling of cache in Process.oneshot() context causes Process instances to return incorrect results.

• #1376, [Windows]: OpenProcess now uses PROCESS_QUERY_LIMITED_INFORMATION where possible, reducing AccessDenied for system processes.

• #1376, [Windows]: check if variable is NULL before free() ing it. (patch by EccoTheFlintstone)

5.4.8 — 2018-10-30

Enhancements

• #1197, [Linux]: cpu_freq() falls back to /proc/cpuinfo if /sys/devices/system/cpu/* is not available.

• #1310, [Linux]: sensors_temperatures() falls back to /sys/class/thermal if /sys/class/hwmon is not available (e.g. Raspberry Pi). (patch by Alex Manuskin)

• #1320, [POSIX]: better compilation support when using g++ instead of GCC. (patch by Jaime Fullaondo)

Bug fixes

• #715: do not print exception on import time in case cpu_times() fails.

• #1004, [Linux]: Process.io_counters() may raise ValueError.

• #1277, [OSX]: available and used memory (virtual_memory()) metrics are not accurate.

• #1294, [Windows]: Process.connections() may sometimes fail with intermittent 0xC0000001. (patch by Sylvain Duchesne)

• #1307, [Linux]: disk_partitions() does not honour PROCFS_PATH.

• #1320, [AIX]: system CPU times (cpu_times()) were being reported with ticks unit as opposed to seconds. (patch by Jaime Fullaondo)

• #1332, [OSX]: psutil debug messages are erroneously printed all the time. (patch by Ilya Yanok)

• #1346, [SunOS]: net_connections() returns an empty list. (patch by Oleksii Shevchuk)

5.4.7 — 2018-08-14

Enhancements

• #1286, [macOS]: OSX constant is now deprecated in favor of new MACOS.

• #1309, [Linux]: added STATUS_PARKED constant for Process.status().

• #1321, [Linux]: disk_io_counters() falls back to /sys/block if /proc/diskstats is not available. (patch by Lawrence Ye)

Bug fixes

• #1209, [macOS]: Process.memory_maps() may fail with EINVAL due to poor task_for_pid() syscall. AccessDenied is now raised instead.

• #1278, [macOS]: Process.threads() incorrectly return microseconds instead of seconds. (patch by Nikhil Marathe)

• #1279, [Linux], [macOS], [BSD]: net_if_stats() may return ENODEV.

• #1294, [Windows]: Process.connections() may sometime fail with MemoryError. (patch by @sylvainduchesne)

• #1305, [Linux]: disk_io_counters() may report inflated r/w bytes values.

• #1309, [Linux]: Process.status() is unable to recognize idle and parked statuses (returns "?").

• #1313, [Linux]: disk_io_counters() can report inflated values due to counting base disk device and its partition(s) twice.

• #1323, [Linux]: sensors_temperatures() may fail with ValueError.

5.4.6 — 2018-06-07

Bug fixes

• #1258, [Windows], [critical]: Process.username() may cause a segfault (Python interpreter crash). (patch by Jean-Luc Migot)

• #1273: net_if_addrs() named tuple’s name has been renamed from snic to snicaddr.

• #1274, [Linux]: there was a small chance Process.children() may swallow AccessDenied exceptions.

5.4.5 — 2018-04-14

Bug fixes

• #1268: setup.py’s extra_require parameter requires latest setuptools version, breaking quite a lot of installations.

5.4.4 — 2018-04-13

Enhancements

• #1239, [Linux]: expose kernel slab memory field for virtual_memory(). (patch by Maxime Mouial)

Bug fixes

• #694, [SunOS]: Process.cmdline() could be truncated at the 15th character when reading it from /proc. An extra effort is made by reading it from process address space first. (patch by Georg Sauthoff)

• #771, [Windows]: cpu_count() (both logical and cores) return a wrong (smaller) number on systems using process groups (> 64 cores).

• #771, [Windows]: cpu_times() with percpu=True return fewer CPUs on systems using process groups (> 64 cores).

• #771, [Windows]: cpu_stats() and cpu_freq() may return incorrect results on systems using process groups (> 64 cores).

• #1193, [SunOS]: return uid/gid from /proc/pid/psinfo if there aren’t enough permissions for /proc/pid/cred. (patch by Georg Sauthoff)

• #1194, [SunOS]: return nice value from psinfo as getpriority() doesn’t support real-time processes. (patch by Georg Sauthoff)

• #1194, [SunOS]: fix double free() in Process.cpu_num(). (patch by Georg Sauthoff)

• #1194, [SunOS]: fix undefined behavior related to strict-aliasing rules and warnings. (patch by Georg Sauthoff)

• #1210, [Linux]: cpu_percent() steal time may remain stuck at 100% due to Linux erroneously reporting a decreased steal time between calls. (patch by Arnon Yaari)

• #1216: fix compatibility with Python 2.6 on Windows (patch by Dan Vinakovsky)

• #1222, [Linux]: Process.memory_full_info() was erroneously summing “Swap:” and “SwapPss:”. Same for “Pss:” and “SwapPss”. Not anymore.

• #1224, [Windows]: Process.wait() may erroneously raise TimeoutExpired.

• #1238, [Linux]: sensors_battery() may return None in case battery is not listed as “BAT0” under /sys/class/power_supply.

• #1240, [Windows]: cpu_times() float loses accuracy in a long running system. (patch by stswandering)

• #1245, [Linux]: sensors_temperatures() may fail with IOError “no such file”.

• #1255, [FreeBSD]: swap_memory() stats were erroneously represented in KB. (patch by Denis Krienbühl)

Backward compatibility

• #771, [Windows]: cpu_count() with logical=False on Windows XP and Vista is no longer supported and returns None.

5.4.3 — 2018-01-01

Enhancements

• #775: disk_partitions() on Windows return mount points.

Bug fixes

• #1193: pids() may return False on macOS.

5.4.2 — 2017-12-07

Enhancements

• #1173: add PSUTIL_DEBUG environment variable to print debug messages on stderr.

• #1177, [macOS]: added support for sensors_battery(). (patch by Arnon Yaari)

• #1183: Process.children() is 2x faster on POSIX and 2.4x faster on Linux.

• #1188: Process.memory_info_ex() now warns with FutureWarning instead of DeprecationWarning.

Bug fixes

• #1152, [Windows]: disk_io_counters() may return an empty dict.

• #1169, [Linux]: users() hostname returns username instead. (patch by janderbrain)

• #1172, [Windows]: make test does not work.

• #1179, [Linux]: Process.cmdline() can now split args for processes that overwrite /proc/pid/cmdline with spaces instead of null bytes.

• #1181, [macOS]: Process.memory_maps() may raise ENOENT.

• #1187, [macOS]: pids() does not return PID 0 on recent macOS versions.

5.4.1 — 2017-11-08

Enhancements

• #1164, [AIX]: add support for Process.num_ctx_switches(). (patch by Arnon Yaari)

• #1053: drop Python 3.3 support (psutil still works but it’s no longer tested).

Bug fixes

• #1150, [Windows]: when a process is terminated now the exit code is set to SIGTERM instead of 0. (patch by Akos Kiss)

• #1151: python -m psutil.tests fail.

• #1154, [AIX], [critical]: psutil won’t compile on AIX 6.1.0. (patch by Arnon Yaari)

• #1167, [Windows]: net_io_counters() packets count now include also non-unicast packets. (patch by Matthew Long)

5.4.0 — 2017-10-12

Enhancements

• #1123, [AIX]: added support for AIX platform. (patch by Arnon Yaari)

Bug fixes

• #1009, [Linux]: sensors_temperatures() may crash with IOError.

• #1012, [Windows]: disk_io_counters() read_time and write_time were expressed in tens of micro seconds instead of milliseconds.

• #1127, [macOS], [critical]: invalid reference counting in Process.open_files() may lead to segfault. (patch by Jakub Bacic)

• #1129, [Linux]: sensors_fans() may crash with IOError. (patch by Sebastian Saip)

• #1131, [SunOS]: fix compilation warnings. (patch by Arnon Yaari)

• #1133, [Windows]: can’t compile on newer versions of Visual Studio 2017 15.4. (patch by Max Bélanger)

• #1138, [Linux]: can’t compile on CentOS 5.0 and RedHat 5.0. (patch by Prodesire)

5.3.1 — 2017-09-10

Enhancements

• #1124: documentation moved to http://psutil.readthedocs.io

Bug fixes

• #1105, [FreeBSD]: psutil does not compile on FreeBSD 12.

• #1125, [BSD]: net_connections() raises TypeError.

Compatibility notes

• #1120: .exe files for Windows are no longer uploaded on PyPI as per PEP-527. Only wheels are provided.

5.3.0 — 2017-09-01

Enhancements

• #802: disk_io_counters() and net_io_counters() no longer wrap (restart from 0). New nowrap argument.

• #928: net_connections() and Process.connections() laddr and raddr are now named tuples.

• #1015: swap_memory() now reads /proc/meminfo instead of sysinfo() syscall, so it works with PROCFS_PATH for containers.

• #1022: users() provides a new pid field.

• #1025: process_iter() accepts new attrs and ad_value parameters to invoke Process.as_dict() inline.

• #1040: implemented full unicode support.

• #1051: disk_usage() on Python 3 is now able to accept bytes.

• #1058: test suite now enables all warnings by default.

• #1060: source distribution now only includes relevant files.

• #1079, [FreeBSD]: net_connections() fd number is now being set for real (instead of -1). (patch by Gleb Smirnoff)

• #1091, [SunOS]: implemented Process.environ(). (patch by Oleksii Shevchuk)

Bug fixes

• #989, [Windows]: boot_time() may return a negative value.

• #1007, [Windows]: boot_time() can have a 1 sec fluctuation between calls. The first call value is now cached.

• #1013, [FreeBSD]: net_connections() may return incorrect PID. (patch by Gleb Smirnoff)

• #1014, [Linux]: Process class can mask legitimate ENOENT exceptions as NoSuchProcess.

• #1016: disk_io_counters() raises RuntimeError on a system with no disks.

• #1017: net_io_counters() raises RuntimeError on a system with no network cards installed.

• #1021, [Linux]: Process.open_files() may erroneously raise NoSuchProcess instead of skipping a file which gets deleted while open files are retrieved.

• #1029, [macOS], [FreeBSD]: Process.connections() with family=unix on Python 3 doesn’t properly handle unicode paths and may raise UnicodeDecodeError.

• #1033, [macOS], [FreeBSD]: memory leak for net_connections() and Process.connections() when retrieving UNIX sockets (kind='unix').

• #1040: fixed many unicode related issues such as UnicodeDecodeError on Python 3 + POSIX and invalid encoded data on Windows.

• #1042, [FreeBSD], [critical]: psutil won’t compile on FreeBSD 12.

• #1044, [macOS]: different Process methods incorrectly raise AccessDenied for zombie processes.

• #1046, [Windows]: disk_partitions() on Windows overrides user’s SetErrorMode.

• #1047, [Windows]: Process.username(): memory leak in case exception is thrown.

• #1048, [Windows]: users()’s host field report an invalid IP address.

• #1050, [Windows]: Process.memory_maps() leaks memory.

• #1055: cpu_count() is no longer cached (CPUs can be disabled at runtime on Linux). Process.cpu_percent() also affected.

• #1058: fixed Python warnings.

• #1062: disk_io_counters() and net_io_counters() raise TypeError if no disks or NICs are installed on the system.

• #1063, [NetBSD]: net_connections() may list incorrect sockets.

• #1064, [NetBSD], [critical]: swap_memory() may segfault in case of error.

• #1065, [OpenBSD], [critical]: Process.cmdline() may raise SystemError.

• #1067, [NetBSD]: Process.cmdline() leaks memory if process has terminated.

• #1069, [FreeBSD]: Process.cpu_num() may return 255 for certain kernel processes.

• #1071, [Linux]: cpu_freq() may raise IOError on old RedHat distros.

• #1074, [FreeBSD]: sensors_battery() raises OSError in case of no battery.

• #1075, [Windows]: net_if_addrs(): inet_ntop() return value is not checked.

• #1077, [SunOS]: net_if_addrs() shows garbage addresses on SunOS 5.10. (patch by Oleksii Shevchuk)

• #1077, [SunOS]: net_connections() does not work on SunOS 5.10. (patch by Oleksii Shevchuk)

• #1079, [FreeBSD]: net_connections() didn’t list locally connected sockets. (patch by Gleb Smirnoff)

• #1085: cpu_count() return value is now checked and forced to None if <= 1.

• #1087: Process.cpu_percent() guard against cpu_count() returning None and assumes 1 instead.

• #1093, [SunOS]: Process.memory_maps() shows wrong 64 bit addresses.

• #1094, [Windows]: fix pid_exists() returning wrong result. All OpenProcess APIs now verify the PID is actually running.

• #1098, [Windows]: Process.wait() may erroneously return sooner, when the PID is still alive.

• #1099, [Windows]: Process.terminate() may raise AccessDenied even if the process already died.

• #1101, [Linux]: sensors_temperatures() may raise ENODEV.

Porting notes

• #1039: returned types consolidation. 1) Windows / Process.cpu_times(): fields #3 and #4 were int instead of float. 2) Linux / FreeBSD / OpenBSD: Process.connections() raddr is now set to "" instead of None when retrieving UNIX sockets.

• #1040: all strings are encoded by using OS fs encoding.

• #1040: the following Windows APIs on Python 2 now return a string instead of unicode: Process.memory_maps()’s path field, WindowsService.binpath(), WindowsService.description(), WindowsService.display_name(), WindowsService.username().

5.2.2 — 2017-04-10

Bug fixes

• #1000: fixed some setup.py warnings.

• #1002, [SunOS]: remove C macro which will not be available on new Solaris versions. (patch by Danek Duvall)

• #1004, [Linux]: Process.io_counters() may raise ValueError.

• #1006, [Linux]: cpu_freq() may return None on some Linux versions does not support the function. Let’s not make the function available instead.

• #1009, [Linux]: sensors_temperatures() may raise OSError.

• #1010, [Linux]: virtual_memory() may raise ValueError on Ubuntu 14.04.

5.2.1 — 2017-03-24

Bug fixes

• #981, [Linux]: cpu_freq() may return an empty list.

• #993, [Windows]: Process.memory_maps() on Python 3 may raise UnicodeDecodeError.

• #996, [Linux]: sensors_temperatures() may not show all temperatures.

• #997, [FreeBSD]: virtual_memory() may fail due to missing sysctl parameter on FreeBSD 12.

5.2.0 — 2017-03-05

Enhancements

• #971, [Linux]: Add sensors_fans() function. (patch by Nicolas Hennion)

• #976, [Windows]: Process.io_counters() has 2 new fields: other_count and other_bytes.

• #976, [Linux]: Process.io_counters() has 2 new fields: read_chars and write_chars.

Bug fixes

• #872, [Linux]: can now compile on Linux by using MUSL C library.

• #985, [Windows]: Fix a crash in Process.open_files() when the worker thread for NtQueryObject times out.

• #986, [Linux]: Process.cwd() may raise NoSuchProcess instead of ZombieProcess.

5.1.3 — 2017-02-07

Bug fixes

• #971, [Linux]: sensors_temperatures() didn’t work on CentOS 7.

• #973, [critical]: cpu_percent() may raise ZeroDivisionError.

5.1.2 — 2017-02-03

Bug fixes

• #966, [Linux]: sensors_battery() power_plugged may erroneously return None on Python 3.

• #968, [Linux]: disk_io_counters() raises TypeError on Python 3.

• #970, [Linux]: sensors_battery() name and label fields on Python 3 are bytes instead of str.

5.1.1 — 2017-02-03

Enhancements

• #966, [Linux]: sensors_battery() percent is a float and is more precise.

Bug fixes

• #964, [Windows]: Process.username() and users() may return badly decoded character on Python 3.

• #965, [Linux]: disk_io_counters() may miscalculate sector size and report the wrong number of bytes read and written.

• #966, [Linux]: sensors_battery() may fail with FileNotFoundError.

• #966, [Linux]: sensors_battery() power_plugged may lie.

5.1.0 — 2017-02-01

Enhancements

• #357: added Process.cpu_num() (what CPU a process is on).

• #371: added sensors_temperatures() (Linux only).

• #941: added cpu_freq() (CPU frequency).

• #955: added sensors_battery() (Linux, Windows, only).

• #956: Process.cpu_affinity() can now be passed [] argument as an alias to set affinity against all eligible CPUs.

Bug fixes

• #687, [Linux]: pid_exists() no longer returns True if passed a process thread ID.

• #948: cannot install psutil with PYTHONOPTIMIZE=2.

• #950, [Windows]: Process.cpu_percent() was calculated incorrectly and showed higher number than real usage.

• #951, [Windows]: the uploaded wheels for Python 3.6 64 bit didn’t work.

• #959: psutil exception objects could not be pickled.

• #960: Popen wait() did not return the correct negative exit status if process is killed by a signal.

• #961, [Windows]: WindowsService.description() method may fail with ERROR_MUI_FILE_NOT_FOUND.

5.0.1 — 2016-12-21

Enhancements

• #939: tar.gz distribution went from 1.8M to 258K.

• #811, [Windows]: provide a more meaningful error message if trying to use psutil on unsupported Windows XP.

Bug fixes

• #609, [SunOS], [critical]: psutil does not compile on Solaris 10.

• #936, [Windows]: fix compilation error on VS 2013 (patch by Max Bélanger).

• #940, [Linux]: cpu_percent() and cpu_times_percent() was calculated incorrectly as iowait, guest and guest_nice times were not properly taken into account.

• #944, [OpenBSD]: pids() was omitting PID 0.

5.0.0 — 2016-11-06

Note

psutil 5.0 introduces breaking API changes. See the migration guide if upgrading from 4.x.

Enhncements

• #799: new Process.oneshot() context manager (+2x faster in general, +2x to +6x on Windows).

• #943: better error message in case of version conflict on import.

Bug fixes

• #932, [NetBSD]: net_connections() and Process.connections() may fail without raising an exception.

• #933, [Windows]: memory leak in cpu_stats() and WindowsService.description() method.

4.4.2 — 2016-10-26

Bug fixes

• #931, [critical]: psutil no longer compiles on Solaris.

4.4.1 — 2016-10-25

Bug fixes

• #927, [critical]: Popen __del__ may cause maximum recursion depth error.

4.4.0 — 2016-10-23

Enhancements

• #874, [Windows]: make net_if_addrs() also return the netmask.

• #887, [Linux]: virtual_memory() available and used are more precise and match free utility. Also handles LXC containers.

• #891: scripts/procinfo.py has been updated and provides a lot more info.

Bug fixes

• #514, [macOS], [critical]: Process.memory_maps() can segfault.

• #783, [macOS]: Process.status() may erroneously return STATUS_RUNNING for zombie processes.

• #798, [Windows]: Process.open_files() returns and empty list on Windows 10.

• #825, [Linux]: Process.cpu_affinity(): fix possible double close and use of unopened socket.

• #880, [Windows]: fix race condition inside net_connections().

• #885: ValueError is raised if a negative integer is passed to cpu_percent() functions.

• #892, [Linux], [critical]: Process.cpu_affinity() with [-1] as arg raises SystemError with no error set; now ValueError is raised.

• #906, [BSD]: disk_partitions() with all=False returned an empty list. Now the argument is ignored and all partitions are always returned.

• #907, [FreeBSD]: Process.exe() may fail with OSError ENOENT.

• #908, [macOS], [BSD]: different process methods could errounesuly mask the real error for high-privileged PIDs and raise NoSuchProcess and AccessDenied instead of OSError and RuntimeError.

• #909, [macOS]: Process.open_files() and Process.connections() methods may raise OSError with no exception set if process is gone.

• #916, [macOS]: fix many compilation warnings.

4.3.1 — 2016-09-01

Enhancements

• #881: make install now works also when using a virtual env.

Bug fixes

• #854: Process.as_dict() raises ValueError if passed an erroneous attrs name.

• #857, [SunOS]: Process.cpu_times(), Process.cpu_percent(), Process.threads() and Process.memory_maps() may raise RuntimeError if attempting to query a 64bit process with a 32bit Python. “Null” values are returned as a fallback.

• #858: Process.as_dict() should not call Process.memory_info_ex() because it’s deprecated.

• #863, [Windows]: Process.memory_maps() truncates addresses above 32 bits.

• #866, [Windows]: win_service_iter() and services in general are not able to handle unicode service names / descriptions.

• #869, [Windows]: Process.wait() may raise TimeoutExpired with wrong timeout unit (ms instead of sec).

• #870, [Windows]: handle leak inside psutil_get_process_data.

4.3.0 — 2016-06-18

Enhancements

• #819, [Linux]: different speedup improvements: Process.ppid() +20% faster. Process.status() +28% faster. Process.name() +25% faster. Process.num_threads() +20% faster on Python 3.

Bug fixes

• #810, [Windows]: Windows wheels are incompatible with pip 7.1.2.

• #812, [NetBSD], [critical]: fix compilation on NetBSD-5.x.

• #823, [NetBSD]: virtual_memory() raises TypeError on Python 3.

• #829, [POSIX]: disk_usage() percent field takes root reserved space into account.

• #816, [Windows]: fixed net_io_counters() values wrapping after 4.3GB in Windows Vista (NT 6.0) and above using 64bit values from newer win APIs.

4.2.0 — 2016-05-14

Enhancements

• #795, [Windows]: new APIs to deal with Windows services: win_service_iter() and win_service_get().

• #800, [Linux]: virtual_memory() returns a new shared field.

• #819, [Linux]: speedup /proc parsing: Process.ppid() +20% faster. Process.status() +28% faster. Process.name() +25% faster. Process.num_threads() +20% faster on Python 3.

Bug fixes

• #797, [Linux]: net_if_stats() may raise OSError for certain NIC cards.

• #813: Process.as_dict() should ignore extraneous attribute names which gets attached to the Process instance.

4.1.0 — 2016-03-12

Enhancements

• #777, [Linux]: Process.open_files() on Linux return 3 new fields: position, mode and flags.

• #779: Process.cpu_times() returns two new fields, children_user and children_system (always set to 0 on macOS and Windows).

• #789, [Windows]: cpu_times() return two new fields: interrupt and dpc. Same for cpu_times_percent().

• #792: new cpu_stats() function returning number of CPU ctx_switches, interrupts, soft_interrupts and syscalls.

Bug fixes

• #774, [FreeBSD]: net_io_counters() dropout is no longer set to 0 if the kernel provides it.

• #776, [Linux]: Process.cpu_affinity() may erroneously raise NoSuchProcess. (patch by @wxwright)

• #780, [macOS]: psutil does not compile with some GCC versions.

• #786: net_if_addrs() may report incomplete MAC addresses.

• #788, [NetBSD]: virtual_memory() buffers and shared values were set to 0.

• #790, [macOS], [critical]: psutil won’t compile on macOS 10.4.

4.0.0 — 2016-02-17

Enhancements

• #523, [Linux], [FreeBSD]: disk_io_counters() return a new busy_time field.

• #660, [Windows]: make.bat is smarter in finding alternative VS install locations. (patch by @mpderbec)

• #732: Process.environ(). (patch by Frank Benkstein)

• #753, [Linux], [macOS], [Windows]: process USS and PSS (Linux) “real” memory stats. (patch by Eric Rahm)

• #755: Process.memory_percent() memtype parameter.

• #758: tests now live in psutil namespace.

• #760: expose OS constants (LINUX, OSX, etc.)

• #756, [Linux]: disk_io_counters() return 2 new fields: read_merged_count and write_merged_count.

• #762: add scripts/procsmem.py.

Bug fixes

• #685, [Linux]: virtual_memory() provides wrong results on systems with a lot of physical memory.

• #704, [SunOS]: psutil does not compile on Solaris sparc.

• #734: on Python 3 invalid UTF-8 data is not correctly handled for Process.name(), Process.cwd(), Process.exe(), Process.cmdline() and Process.open_files() methods resulting in UnicodeDecodeError exceptions. 'surrogateescape' error handler is now used as a workaround for replacing the corrupted data.

• #737, [Windows]: when the bitness of psutil and the target process was different, Process.cmdline() and Process.cwd() could return a wrong result or incorrectly report an AccessDenied error.

• #741, [OpenBSD]: psutil does not compile on mips64.

• #751, [Linux]: fixed call to Py_DECREF on possible NULL object.

• #754, [Linux]: Process.cmdline() can be wrong in case of zombie process.

• #759, [Linux]: Process.memory_maps() may return paths ending with " (deleted)".

• #761, [Windows]: boot_time() wraps to 0 after 49 days.

• #764, [NetBSD]: fix compilation on NetBSD-6.x.

• #766, [Linux]: net_connections() can’t handle malformed /proc/net/unix file.

• #767, [Linux]: disk_io_counters() may raise ValueError on 2.6 kernels and it’s broken on 2.4 kernels.

• #770, [NetBSD]: disk_io_counters() metrics didn’t update.

3.4.2 — 2016-01-20

Enhancements

• #728, [SunOS]: exposed PROCFS_PATH constant to change the default location of /proc filesystem.

Bug fixes

• #724, [FreeBSD]: virtual_memory() total is incorrect.

• #730, [FreeBSD], [critical]: virtual_memory() crashes with “OSError: [Errno 12] Cannot allocate memory”.

3.4.1 — 2016-01-15

Enhancements

• #557, [NetBSD]: added NetBSD support. (contributed by Ryo Onodera and Thomas Klausner)

• #708, [Linux]: net_connections() and Process.connections() on Python 2 can be up to 3x faster in case of many connections. Also Process.memory_maps() is slightly faster.

• #718: process_iter() is now thread safe.

Bug fixes

• #714, [OpenBSD]: virtual_memory() cached value was always set to 0.

• #715, [critical]: don’t crash at import time if cpu_times() fail for some reason.

• #717, [Linux]: Process.open_files() fails if deleted files still visible.

• #722, [Linux]: swap_memory() no longer crashes if sin / sout can’t be determined due to missing /proc/vmstat.

• #724, [FreeBSD]: virtual_memory() total is slightly incorrect.

3.3.0 — 2015-11-25

Enhancements

• #558, [Linux]: exposed PROCFS_PATH constant to change the default location of /proc filesystem.

• #615, [OpenBSD]: added OpenBSD support. (contributed by Landry Breuil)

Bug fixes

• #692, [POSIX]: Process.name() is no longer cached as it may change.

3.2.2 — 2015-10-04

Bug fixes

• #517, [SunOS]: net_io_counters() failed to detect network interfaces correctly on Solaris 10

• #541, [FreeBSD]: disk_io_counters() r/w times were expressed in seconds instead of milliseconds. (patch by dasumin)

• #610, [SunOS]: fix build and tests on Solaris 10

• #623, [Linux]: process or system connections raises ValueError if IPv6 is not supported by the system.

• #678, [Linux], [critical]: can’t install psutil due to bug in setup.py.

• #688, [Windows]: compilation fails with MSVC 2015, Python 3.5. (patch by Mike Sarahan)

3.2.1 — 2015-09-03

Bug fixes

• #677, [Linux], [critical]: can’t install psutil due to bug in setup.py.

3.2.0 — 2015-09-02

Enhancements

• #644, [Windows]: added support for CTRL_C_EVENT and CTRL_BREAK_EVENT signals to use with Process.send_signal().

• #648: CI test integration for macOS. (patch by Jeff Tang)

• #663, [POSIX]: net_if_addrs() now returns point-to-point (VPNs) addresses.

• #655, [Windows]: fix various unicode handling issues. On Python 2, string APIs now return encoded strings using sys.getfilesystemencoding().

Bug fixes

• #513, [Linux]: fixed integer overflow for RLIM_INFINITY

• #641, [Windows]: fixed many compilation warnings. (patch by Jeff Tang)

• #652, [Windows]: net_if_addrs() UnicodeDecodeError in case of non-ASCII NIC names.

• #655, [Windows]: net_if_stats() UnicodeDecodeError in case of non-ASCII NIC names.

• #659, [Linux]: compilation error on Suse 10. (patch by @maozguttman)

• #664, [Linux]: compilation error on Alpine Linux. (patch by Bart van Kleef)

• #670, [Windows]: segfgault of net_if_addrs() in case of non-ASCII NIC names. (patch by sk6249)

• #672, [Windows]: compilation fails if using Windows SDK v8.0. (patch by Steven Winfield)

• #675, [Linux]: net_connections(): UnicodeDecodeError may occur when listing UNIX sockets.

3.1.1 — 2015-07-15

Bug fixes

• #603, [Linux]: Process.ionice() set value range is incorrect. (patch by spacewander)

• #645, [Linux]: cpu_times_percent() may produce negative results.

• #656: from psutil import * does not work.

3.1.0 — 2015-07-15

Enhancements

• #534, [Linux]: disk_partitions() added support for ZFS filesystems.

• #646, [Windows]: continuous tests integration for Windows with https://ci.appveyor.com/project/giampaolo/psutil.

• #647: new dev guide: https://github.com/giampaolo/psutil/blob/master/docs/devguide.rst

• #651: continuous code quality test integration with scrutinizer-ci.com

Bug fixes

• #340, [Windows], [critical]: Process.open_files() no longer hangs (uses a thread with timeout). (patch by Jeff Tang)

• #627, [Windows]: Process.name() no longer raises AccessDenied for pids owned by another user.

• #636, [Windows]: Process.memory_info() raise AccessDenied.

• #637, [POSIX]: raise exception if trying to send signal to PID 0 as it will affect os.getpid() ‘s process group and not PID 0.

• #639, [Linux]: Process.cmdline() can be truncated.

• #640, [Linux]: *connections functions may swallow errors and return an incomplete list of connections.

• #642: repr() of exceptions is incorrect.

• #653, [Windows]: add inet_ntop() function for Windows XP to support IPv6.

• #641, [Windows]: replace deprecated string functions with safe equivalents.

3.0.1 — 2015-06-18

Bug fixes

• #632, [Linux]: better error message if cannot parse process UNIX connections.

• #634, [Linux]: Process.cmdline() does not include empty string arguments.

• #635, [POSIX], [critical]: crash on module import if enum package is installed on Python < 3.4.

3.0.0 — 2015-06-13

Enhancements

• #250: new net_if_stats() returning NIC statistics (isup, duplex, speed, mtu).

• #376: new net_if_addrs() returning all NIC addresses a-la ifconfig.

• #469: on Python >= 3.4 IOPRIO_CLASS_* and *_PRIORITY_CLASS constants returned by Process.ionice() and Process.nice() are enums instead of plain integers.

• #581: add .gitignore. (patch by Gabi Davar)

• #582: connection constants returned by net_connections() and Process.connections() were turned from int to enums on Python > 3.4.

• #587: move native extension into the package.

• #589: Process.cpu_affinity() accepts any kind of iterable (set, tuple, …), not only lists.

• #594: all deprecated APIs were removed.

• #599, [Windows]: Process.name() can now be determined for all processes even when running as a limited user.

• #602: pre-commit GIT hook.

• #629: enhanced support for pytest and nose test runners.

• #616, [Windows]: add inet_ntop() function for Windows XP.

Bug fixes

• #428, [POSIX], [critical]: correct handling of zombie processes on POSIX. Introduced new ZombieProcess exception class.

• #512, [BSD], [critical]: fix segfault in net_connections().

• #555, [Linux]: users() correctly handles ":0" as an alias for "localhost".

• #579, [Windows]: fixed Process.open_files() for PID > 64K.

• #579, [Windows]: fixed many compiler warnings.

• #585, [FreeBSD]: net_connections() may raise KeyError.

• #586, [FreeBSD], [critical]: Process.cpu_affinity() segfaults on set in case an invalid CPU number is provided.

• #593, [FreeBSD], [critical]: Process.memory_maps() segfaults.

• #606: Process.parent() may swallow NoSuchProcess exceptions.

• #611, [SunOS]: net_io_counters() has send and received swapped

• #614, [Linux]:: cpu_count() with logical=False return the number of sockets instead of cores.

• #618, [SunOS]: swap tests fail on Solaris when run as normal user.

• #628, [Linux]: Process.name() truncates string in case it contains spaces or parentheses.

2.2.1 — 2015-02-02

Bug fixes

• #572, [Linux]: fix “ValueError: ambiguous inode with multiple PIDs references” for Process.connections(). (patch by Bruno Binet)

2.2.0 — 2015-01-06

Enhancements

• #521: drop support for Python 2.4 and 2.5.

• #553: add scripts/pstree.py.

• #564: C extension version mismatch is now detected at import time.

• #568: add scripts/pidof.py.

• #569, [FreeBSD]: add support for Process.cpu_affinity() on FreeBSD.

Bug fixes

• #496, [SunOS], [critical]: can’t import psutil.

• #547, [POSIX]: Process.username() may raise KeyError if UID can’t be resolved.

• #551, [Windows]: get rid of the unicode hack for net_io_counters() NIC names.

• #556, [Linux]: lots of file handles were left open.

• #561, [Linux]: net_connections() might skip some legitimate UNIX sockets. (patch by spacewander)

• #565, [Windows]: use proper encoding for Process.username() and users(). (patch by Sylvain Mouquet)

• #567, [Linux]: in the alternative implementation of Process.cpu_affinity() PyList_Append and Py_BuildValue return values are not checked.

• #569, [FreeBSD]: fix memory leak in cpu_count() with logical=False.

• #571, [Linux]: Process.open_files() might swallow AccessDenied exceptions and return an incomplete list of open files.

2.1.3 — 2014-09-26

• #536, [Linux], [critical]: fix “undefined symbol: CPU_ALLOC” compilation error.

2.1.2 — 2014-09-21

Enhancements

• #407: project moved from Google Code to Github; code moved from Mercurial to Git.

• #492: use tox to run tests on multiple Python versions. (patch by msabramo)

• #505, [Windows]: distribution as wheel packages.

• #511: add scripts/ps.py.

Bug fixes

• #340, [Windows]: Process.open_files() no longer hangs. (patch by Jeff Tang)

• #501, [Windows]: disk_io_counters() may return negative values.

• #503, [Linux]: in rare conditions Process.exe(), Process.open_files() and Process.connections() can raise OSError(ESRCH) instead of NoSuchProcess.

• #504, [Linux]: can’t build RPM packages via setup.py

• #506, [Linux], [critical]: Python 2.4 support was broken.

• #522, [Linux]: Process.cpu_affinity() might return EINVAL. (patch by David Daeschler)

• #529, [Windows]: Process.exe() may raise unhandled WindowsError exception for PIDs 0 and 4. (patch by Jeff Tang)

• #530, [Linux]: disk_io_counters() may crash on old Linux distros (< 2.6.5) (patch by Yaolong Huang)

• #533, [Linux]: Process.memory_maps() may raise TypeError on old Linux distros.

2.1.1 — 2014-04-30

Bug fixes

• #446, [Windows]: fix encoding error when using net_io_counters() on Python 3. (patch by Szigeti Gabor Niif)

• #460, [Windows]: net_io_counters() wraps after 4G.

• #491, [Linux]: net_connections() exceptions. (patch by Alexander Grothe)

2.1.0 — 2014-04-08

Enhancements

• #387: system-wide open connections a-la netstat (add net_connections()).

Bug fixes

• #421, [SunOS], [critical]: psutil does not compile on SunOS 5.10. (patch by Naveed Roudsari)

• #489, [Linux]: disk_partitions() return an empty list.

2.0.0 — 2014-03-10

Enhancements

• #424, [Windows]: installer for Python 3.X 64 bit.

• #427: add cpu_count().

• #447: wait_procs() timeout parameter is now optional.

• #452: make Process instances hashable and usable with set() s.

• #453: tests on Python < 2.7 require unittest2 module.

• #459: add a Makefile for running tests and other repetitive tasks (also on Windows).

• #463: make timeout parameter of cpu_percent* functions default to 0.0 ‘cause it’s a common trap to introduce slowdowns.

• #468: move documentation to readthedocs.com.

• #477: Process.cpu_percent() is about 30% faster. (suggested by crusaderky)

• #478, [Linux]: almost all APIs are about 30% faster on Python 3.X.

• #479: long deprecated psutil.error module is gone; exception classes now live in psutil namespace only.

Bug fixes

• #193: Popen constructor can throw an exception if the spawned process terminates quickly.

• #340, [Windows]: Process.open_files() no longer hangs. (patch by jtang@vahna.net)

• #443, [Linux]: fix a potential overflow issue for Process.cpu_affinity() (set) on systems with more than 64 CPUs.

• #448, [Windows]: Process.children() and Process.ppid() memory leak (patch by Ulrich Klank).

• #457, [POSIX]: pid_exists() always returns True for PID 0.

• #461: named tuples are not pickle-able.

• #466, [Linux]: Process.exe() improper null bytes handling. (patch by Gautam Singh)

• #470: wait_procs() might not wait. (patch by @crusaderky)

• #471, [Windows]: Process.exe() improper unicode handling. (patch by alex@mroja.net)

• #473: Popen wait() method does not set returncode attribute.

• #474, [Windows]: Process.cpu_percent() is no longer capped at 100%.

• #476, [Linux]: encoding error for Process.name() and Process.cmdline().

API changes

For the sake of consistency a lot of psutil APIs have been renamed. In most cases accessing the old names will work but it will cause a DeprecationWarning.

• psutil.* module level constants have being replaced by functions:

  Old name	Replacement
  psutil.NUM_CPUS	psutil.cpu_count()
  psutil.BOOT_TIME	psutil.boot_time()
  psutil.TOTAL_PHYMEM	virtual_memory.total

• Renamed psutil.* functions:

  Old name	Replacement
  psutil.get_pid_list()	psutil.pids()
  psutil.get_users()	psutil.users()
  psutil.get_boot_time()	psutil.boot_time()

• All Process get_* methods lost the get_ prefix. E.g. get_ext_memory_info() was renamed to memory_info_ex(). Assuming p = psutil.Process():

  Old name	Replacement
  p.get_children()	p.children()
  p.get_connections()	p.connections()
  p.get_cpu_affinity()	p.cpu_affinity()
  p.get_cpu_percent()	p.cpu_percent()
  p.get_cpu_times()	p.cpu_times()
  p.get_ext_memory_info()	p.memory_info_ex()
  p.get_io_counters()	p.io_counters()
  p.get_ionice()	p.ionice()
  p.get_memory_info()	p.memory_info()
  p.get_memory_maps()	p.memory_maps()
  p.get_memory_percent()	p.memory_percent()
  p.get_nice()	p.nice()
  p.get_num_ctx_switches()	p.num_ctx_switches()
  p.get_num_fds()	p.num_fds()
  p.get_num_threads()	p.num_threads()
  p.get_open_files()	p.open_files()
  p.get_rlimit()	p.rlimit()
  p.get_threads()	p.threads()
  p.getcwd()	p.cwd()

• All Process set_* methods lost the set_ prefix. Assuming p = psutil.Process():

  Old name	Replacement
  p.set_nice()	p.nice(value)
  p.set_ionice()	p.ionice(ioclass, value=None)
  p.set_cpu_affinity()	p.cpu_affinity(cpus)
  p.set_rlimit()	p.rlimit(resource, limits=None)

• Except for pid, all Process class properties have been turned into methods. This is the only case which there are no aliases. Assuming p = psutil.Process():

  Old name	Replacement
  p.name	p.name()
  p.parent	p.parent()
  p.ppid	p.ppid()
  p.exe	p.exe()
  p.cmdline	p.cmdline()
  p.status	p.status()
  p.uids	p.uids()
  p.gids	p.gids()
  p.username	p.username()
  p.create_time	p.create_time()

• timeout parameter of cpu_percent* functions defaults to 0.0 instead of 0.1.

• long deprecated psutil.error module is gone; exception classes now live in “psutil” namespace only.

• Process instances’ retcode attribute returned by wait_procs() has been renamed to returncode for consistency with subprocess.Popen.

1.2.1 — 2013-11-25

Bug fixes

• #348, [Windows], [critical]: fixed “ImportError: DLL load failed” occurring on module import on Windows XP.

• #425, [SunOS], [critical]: crash on import due to failure at determining BOOT_TIME.

• #443, [Linux]: Process.cpu_affinity() can’t set affinity on systems with more than 64 cores.

1.2.0 — 2013-11-20

Enhancements

• #439: assume os.getpid() if no argument is passed to Process class constructor.

• #440: new wait_procs() utility function which waits for multiple processes to terminate.

Bug fixes

• #348, [Windows]: fix “ImportError: DLL load failed” occurring on module import on Windows XP / Vista.

1.1.3 — 2013-11-07

Bug fixes

• #442, [Linux], [critical]: psutil won’t compile on certain version of Linux because of missing prlimit(2) syscall.

1.1.2 — 2013-10-22

Bug fixes

• #442, [Linux], [critical]: psutil won’t compile on Debian 6.0 because of missing prlimit(2) syscall.

1.1.1 — 2013-10-08

Bug fixes

• #442, [Linux], [critical]: psutil won’t compile on kernels < 2.6.36 due to missing prlimit(2) syscall.

1.1.0 — 2013-09-28

Enhancements

• #410: host tar.gz and Windows binary files are on PyPI.

• #412, [Linux]: add Process.rlimit().

• #415, [Windows]: Process.children() is an order of magnitude faster.

• #426, [Windows]: Process.name() is an order of magnitude faster.

• #431, [POSIX]: Process.name() is slightly faster because it unnecessarily retrieved also Process.cmdline().

Bug fixes

• #391, [Windows]: cpu_times_percent() returns negative percentages.

• #408: STATUS_* and CONN_* constants don’t properly serialize on JSON.

• #411, [Windows]: scripts/disk_usage.py may pop-up a GUI error.

• #413, [Windows]: Process.memory_info() leaks memory.

• #414, [Windows]: Process.exe() on Windows XP may raise ERROR_INVALID_PARAMETER.

• #416: disk_usage() doesn’t work well with unicode path names.

• #430, [Linux]: Process.io_counters() report wrong number of r/w syscalls.

• #435, [Linux]: net_io_counters() might report erreneous NIC names.

• #436, [Linux]: net_io_counters() reports a wrong dropin value.

API changes

• #408: turn STATUS_* and CONN_* constants into plain Python strings.

1.0.1 — 2013-07-12

Bug fixes

• #405: net_io_counters() pernic=True no longer works as intended in 1.0.0.

1.0.0 — 2013-07-10

Enhancements

• #18, [SunOS]: add Solaris support (yay!) (thanks Justin Venus)

• #367: Process.connections() status strings are now constants.

• #380: test suite exits with non-zero on failure. (patch by floppymaster)

• #391: introduce unittest2 facilities and provide workarounds if unittest2 is not installed (Python < 2.7).

Bug fixes

• #374, [Windows]: negative memory usage reported if process uses a lot of memory.

• #379, [Linux]: Process.memory_maps() may raise ValueError.

• #394, [macOS]: mapped memory regions of Process.memory_maps() report incorrect file name.

• #404, [Linux]: sched_*affinity() are implicitly declared. (patch by Arfrever)

API changes

• Process.connections() status field is no longer a string but a constant object (psutil.CONN_*).

• Process.connections() local_address and remote_address fields renamed to laddr and raddr.

• psutil.network_io_counters() renamed to net_io_counters().

0.7.1 — 2013-05-03

Bug fixes

• #325, [BSD], [critical]: virtual_memory() can raise SystemError. (patch by Jan Beich)

• #370, [BSD]: Process.connections() requires root. (patch by John Baldwin)

• #372, [BSD]: different process methods raise NoSuchProcess instead of AccessDenied.

0.7.0 — 2013-04-12

Enhancements

• #233: code migrated to Mercurial (yay!)

• #246: psutil.error module is deprecated and scheduled for removal.

• #328, [Windows]: Process.ionice() support.

• #359: add boot_time() as a substitute of psutil.BOOT_TIME since the latter cannot reflect system clock updates.

• #361, [Linux]: cpu_times() now includes new steal, guest and guest_nice fields available on recent Linux kernels. Also, cpu_percent() is more accurate.

• #362: add cpu_times_percent() (per-CPU-time utilization as a percentage).

Bug fixes

• #234, [Windows]: disk_io_counters() fails to list certain disks.

• #264, [Windows]: use of disk_partitions() may cause a message box to appear.

• #313, [Linux], [critical]: virtual_memory() and swap_memory() can crash on certain exotic Linux flavors having an incomplete /proc interface. If that’s the case we now set the unretrievable stats to 0 and raise RuntimeWarning instead.

• #315, [macOS]: fix some compilation warnings.

• #317, [Windows]: cannot set process CPU affinity above 31 cores.

• #319, [Linux]: Process.memory_maps() raises KeyError ‘Anonymous’ on Debian squeeze.

• #321, [POSIX]: Process.ppid() property is no longer cached as the kernel may set the PPID to 1 in case of a zombie process.

• #323, [macOS]: disk_io_counters() read_time and write_time parameters were reporting microseconds not milliseconds. (patch by Gregory Szorc)

• #331: Process.cmdline() is no longer cached after first access as it may change.

• #333, [macOS]: leak of Mach ports (patch by @rsesek)

• #337, [Linux], [critical]: Process methods not working because of a poor /proc implementation will raise NotImplementedError rather than RuntimeError and Process.as_dict() will not blow up. (patch by Curtin1060)

• #338, [Linux]: disk_io_counters() fails to find some disks.

• #339, [FreeBSD]: get_pid_list() can allocate all the memory on system.

• #341, [Linux], [critical]: psutil might crash on import due to error in retrieving system terminals map.

• #344, [FreeBSD]: swap_memory() might return incorrect results due to kvm_open(3) not being called. (patch by Jean Sebastien)

• #338, [Linux]: disk_io_counters() fails to find some disks.

• #351, [Windows]: if psutil is compiled with MinGW32 (provided installers for py2.4 and py2.5 are) disk_io_counters() will fail. (Patch by m.malycha)

• #353, [macOS]: users() returns an empty list on macOS 10.8.

• #356: Process.parent() now checks whether parent PID has been reused in which case returns None.

• #365: Process.nice() (set) should check PID has not been reused by another process.

• #366, [FreeBSD], [critical]: Process.memory_maps(), Process.num_fds(), Process.open_files() and Process.cwd() methods raise RuntimeError instead of AccessDenied.

API changes

• Process.cmdline() property is no longer cached after first access.

• Process.ppid() property is no longer cached after first access.

• [Linux] Process methods not working because of a poor /proc implementation will raise NotImplementedError instead of RuntimeError.

• psutil.error module is deprecated and scheduled for removal.

0.6.1 — 2012-08-16

Enhancements

• #316: Process.cmdline() property now makes a better job at guessing the process executable from the cmdline.

Bug fixes

• #316: Process.exe() was resolved in case it was a symlink.

• #318, [critical]: Python 2.4 compatibility was broken.

API changes

• Process.exe() can now return an empty string instead of raising AccessDenied.

• Process.exe() is no longer resolved in case it’s a symlink.

0.6.0 — 2012-08-13

Enhancements

• #216, [POSIX]: add Process.connections() UNIX sockets support.

• #220, [FreeBSD]: net_connections() has been rewritten in C and no longer requires lsof.

• #222, [macOS]: add support for Process.cwd().

• #261: add Process.memory_info_ex().

• #295, [macOS]: Process.exe() path is now determined by asking the OS instead of being guessed from Process.cmdline().

• #297, [macOS]: Process.name(), Process.memory_info(), Process.memory_percent(), Process.cpu_times(), Process.cpu_percent(), Process.num_threads() no longer raise AccessDenied for other users’ processes and are 2.5x faster.

• #300: add scripts/pmap.py.

• #301: process_iter() now yields processes sorted by their PIDs.

• #302: add Process.num_ctx_switches().

• #303, [Windows]: Process.create_time(), Process.cpu_times(), Process.cpu_percent(), Process.memory_info(), Process.memory_percent(), Process.num_handles(), Process.io_counters() no longer raise AccessDenied for other users’ processes.

• #305: add scripts/netstat.py.

• #311: add virtual_memory() and swap_memory(). Old memory-related functions are deprecated. New example scripts: scripts/free.py and scripts/meminfo.py.

• #312: net_io_counters() adds 4 new fields: errin, errout, dropin and dropout.

Bug fixes

• #298, [macOS], [BSD]: memory leak in Process.num_fds().

• #299: potential memory leak every time PyList_New(0) is used.

• #303, [Windows], [critical]: potential heap corruption in Process.num_threads() and Process.status() methods.

• #305, [FreeBSD], [critical]: can’t compile on FreeBSD 9 due to removal of utmp.h.

• #306, [critical]: at C level, errors are not checked when invoking Py* functions which create or manipulate Python objects leading to potential memory related errors and/or segmentation faults.

• #307, [FreeBSD]: values returned by net_io_counters() are wrong.

• #308, [BSD], [Windows]: psutil.virtmem_usage() wasn’t actually returning information about swap memory usage as it was supposed to do. It does now.

• #309: Process.open_files() might not return files which can not be accessed due to limited permissions. AccessDenied is now raised instead.

API changes

• psutil.phymem_usage() is deprecated (use virtual_memory())

• psutil.virtmem_usage() is deprecated (use swap_memory())

• [Linux]: psutil.phymem_buffers() is deprecated (use virtual_memory())

• [Linux]: psutil.cached_phymem() is deprecated (use virtual_memory())

• [Windows], [BSD]: psutil.virtmem_usage() now returns information about swap memory instead of virtual memory.

0.5.1 — 2012-06-29

Enhancements

• #293, [Windows]: Process.exe() path is now determined by asking the OS instead of being guessed from Process.cmdline().

Bug fixes

• #292, [Linux]: race condition in process Process.open_files(), Process.connections(), Process.threads().

• #294, [Windows]: Process.cpu_affinity() is only able to set CPU #0.

0.5.0 — 2012-06-27

Enhancements

• #195, [Windows]: add Process.num_handles().

• #209: disk_partitions() now provides also mount options.

• #229: add users().

• #238, [Linux], [Windows]: add Process.cpu_affinity().

• #242: add recursive=True to Process.children(): return all process descendants.

• #245, [POSIX]: Process.wait() incrementally consumes less CPU cycles.

• #257, [Windows]: removed Windows 2000 support.

• #258, [Linux]: Process.memory_info() is now 0.5x faster.

• #260: add Process.memory_maps(). (Windows patch by @wj32, macOS patch by Jeremy Whitlock)

• #262, [Windows]: disk_partitions() was slow due to inspecting the floppy disk drive also when parameter is all=False.

• #273: psutil.get_process_list() is deprecated.

• #274: psutil no longer requires 2to3 at installation time in order to work with Python 3.

• #278: add Process.as_dict().

• #281: Process.ppid(), Process.name(), Process.exe(), Process.cmdline() and Process.create_time() are now cached after first access.

• #282: psutil.STATUS_* constants can now be compared by using their string representation.

• #283: speedup Process.is_running() by caching its return value in case the process is terminated.

• #284, [POSIX]: add Process.num_fds().

• #287: process_iter() now caches Process instances between calls.

• #290: Process.nice() property is deprecated in favor of new get_nice() and set_nice() methods.

Bug fixes

• #193: Popen constructor can throw an exception if the spawned process terminates quickly.

• #240, [macOS]: incorrect use of free() for Process.connections().

• #244, [POSIX]: Process.wait() can hog CPU resources if called against a process which is not our children.

• #248, [Linux]: net_io_counters() might return erroneous NIC names.

• #252, [Windows]: Process.cwd() erroneously raise NoSuchProcess for processes owned by another user. It now raises AccessDenied instead.

• #266, [Windows]: psutil.get_pid_list() only shows 1024 processes. (patch by @amoser)

• #267, [macOS]: Process.connections() returns wrong remote address. (Patch by Amoser)

• #272, [Linux]: Process.open_files() potential race condition can lead to unexpected NoSuchProcess exception. Also, we can get incorrect reports of not absolutized path names.

• #275, [Linux]: Process.io_counters() erroneously raise NoSuchProcess on old Linux versions. Where not available it now raises NotImplementedError.

• #286: Process.is_running() doesn’t actually check whether PID has been reused.

• #314: Process.children() can sometimes return non-children.

API changes

• Process.nice property is deprecated in favor of new get_nice() and set_nice() methods.

• psutil.get_process_list() is deprecated.

• Process.ppid(), Process.name(), Process.exe(), Process.cmdline() and Process.create_time() properties of Process class are now cached after being accessed, meaning NoSuchProcess will no longer be raised in case the process is gone in the meantime.

• psutil.STATUS_* constants can now be compared by using their string representation.

0.4.1 — 2011-12-14

Bug fixes

• #228: some example scripts were not working with Python 3.

• #230, [Windows], [macOS]: fix memory leak in Process.connections().

• #232, [Linux]: psutil.phymem_usage() can report erroneous values which are different than free command.

• #236, [Windows]: fix memory/handle leak in Process.memory_info(), Process.suspend() and Process.resume() methods.

0.4.0 — 2011-10-29

Enhancements

• #150: add net_io_counters() (macOS and Windows patch by Jeremy Whitlock)

• #154, [FreeBSD]: add support for Process.cwd().

• #157, [Windows]: provide installer for Python 3.2 64-bit.

• #198: Process.wait() with timeout=0 can now be used to make the function return immediately.

• #206: add disk_io_counters()). (macOS and Windows patch by Jeremy Whitlock)

• #213: add scripts/iotop.py.

• #217: Process.connections() now has a kind argument to filter for connections with different criteria.

• #221, [FreeBSD]: Process.open_files() has been rewritten in C and no longer relies on lsof.

• #223: add scripts/top.py.

• #227: add scripts/nettop.py.

Bug fixes

• #135, [macOS]: psutil cannot create Process object.

• #144, [Linux]: no longer support 0 special PID.

• #188, [Linux]: psutil import error on Linux ARM architectures.

• #194, [POSIX]: Process.cpu_percent() now reports a percentage over 100 on multi core processors.

• #197, [Linux]: Process.connections() is broken on platforms not supporting IPv6.

• #200, [Linux], [critical]: psutil.NUM_CPUS not working on armel and sparc architectures and causing crash on module import.

• #201, [Linux]: Process.connections() is broken on big-endian architectures.

• #211: Process instance can unexpectedly raise NoSuchProcess if tested for equality with another object.

• #218, [Linux], [critical]: crash at import time on Debian 64-bit because of a missing line in /proc/meminfo.

• #226, [FreeBSD], [critical]: crash at import time on FreeBSD 7 and minor.

0.3.0 — 2011-07-08

Enhancements

• #125: add cpu_times() and cpu_percent() per-cpu support.

• #163: add Process.terminal().

• #171: add get_phymem() and get_virtmem(). Old total_*, avail_* and used_* memory functions are deprecated.

• #172: add disk_usage().

• #174: add disk_partitions().

• #179: setuptools is now used in setup.py

Bug fixes

• #159, [Windows]: SetSeDebug() does not close handles or unset impersonation on return.

• #164, [Windows]: Process.wait() raises a TimeoutException when a process returns -1.

• #165: Process.status() raises an unhandled exception.

• #166: Process.memory_info() leaks handles hogging system resources.

• #168: cpu_percent() returns erroneous results when used in non-blocking mode. (patch by Philip Roberts)

• #178, [macOS]: Process.threads() leaks memory.

• #180, [Windows]: Process.num_threads() and Process.threads() methods can raise NoSuchProcess exception while process still exists.

0.2.1 — 2011-03-20

Enhancements

• #64: add Process.io_counters().

• #116: add Process.wait().

• #134: add Process.threads().

• #136: Process.exe() path on FreeBSD is now determined by asking the kernel instead of guessing it from cmdline[0].

• #137: add Process.uids() and Process.gids().

• #140: add boot_time().

• #142: add Process.nice().

• #143: add Process.status().

• #147 [Linux]: add Process.ionice().

• #148: add Popen class combining subprocess.Popen and Process in a single interface.

• #152, [macOS]: Process.open_files() rewritten in C (no longer relies on lsof, 3x faster).

• #153, [macOS]: Process.connections() rewritten in C (no longer relies on lsof, 3x faster).

Bug fixes

• #83, [macOS]: Process.cmdline() is empty on macOS 64-bit.

• #130, [Linux]: a race condition can cause IOError exception be raised on if process disappears between open() and the subsequent read() call.

• #145, [Windows], [critical]: WindowsError was raised instead of AccessDenied when using Process.resume() or Process.suspend().

• #146, [Linux]: Process.exe() property can raise TypeError if path contains NULL bytes.

• #151, [Linux]: Process.exe() and Process.cwd() for PID 0 return inconsistent data.

API changes

• Process uid and gid properties are deprecated in favor of uids and gids properties.

0.2.0 — 2010-11-13

Enhancements

• #79: add Process.open_files().

• #88: total system physical cached memory.

• #88: total system physical memory buffers used by the kernel.

• #91: add Process.send_signal() and Process.terminate() methods.

• #95: NoSuchProcess and AccessDenied exception classes now provide pid, name and msg attributes.

• #97: add Process.children().

• #98: Process.cpu_times() and Process.memory_info() now return a named tuple instead of a tuple.

• #103: add Process.connections().

• #107, [Windows]: add support for Windows 64 bit. (patch by cjgohlke)

• #111: add Process.exe().

• #113: exception messages now include Process.name() and Process.pid.

• #114, [Windows]: Process.username() rewritten in C (no longer uses WMI, much faster, pywin32 no longer required). (patch by @wj32)

• #117, [Windows]: added support for Windows 2000.

• #123: cpu_percent() and Process.cpu_percent() accept a new interval parameter.

• #129: add Process.threads().

Bug fixes

• #80: fixed warnings when installing psutil with easy_install.

• #81, [Windows]: psutil fails to compile with Visual Studio.

• #94: Process.suspend() raises OSError instead of AccessDenied.

• #86, [FreeBSD]: psutil didn’t compile against FreeBSD 6.x.

• #102, [Windows]: orphaned process handles obtained by using OpenProcess in C were left behind every time Process class was instantiated.

• #111, [POSIX]: path and name Process properties report truncated or erroneous values on POSIX.

• #120, [macOS]: cpu_percent() always returning 100%.

• #112: uid and gid properties don’t change if process changes effective user/group id at some point.

• #126: Process.ppid(), Process.uids(), Process.gids(), Process.name(), Process.exe(), Process.cmdline() and Process.create_time() properties are no longer cached and correctly raise NoSuchProcess exception if the process disappears.

API changes

• psutil.Process.path property is deprecated and works as an alias for psutil.Process.exe property.

• Process.kill(): signal argument was removed - to send a signal to the process use Process.send_signal() method instead.

• Process.memory_info() returns a named tuple instead of a tuple.

• cpu_times() returns a named tuple instead of a tuple.

• Add Process.open_files(), Process.connections(), Process.send_signal() and Process.terminate().

• Process.ppid(), Process.uids(), Process.gids(), Process.name(), Process.exe(), Process.cmdline() and Process.create_time() properties are no longer cached and raise NoSuchProcess exception if process disappears.

• cpu_percent() no longer returns immediately (see #123).

• Process.cpu_percent() and cpu_percent() no longer returns immediately by default (see #123).

0.1.3 — 2010-03-02

Enhancements

• #14: Process.username().

• #51, [Linux], [Windows]: add Process.cwd().

• #59: Process.is_running() is now 10 times faster.

• #61, [FreeBSD]: added support for FreeBSD 64 bit.

• #71: add Process.suspend() and Process.resume().

• #75: Python 3 support.

Bug fixes

• #36: Process.cpu_times() and Process.memory_info() functions succeeded. also for dead processes while a NoSuchProcess exception is supposed to be raised.

• #48, [FreeBSD]: incorrect size for MIB array defined in getcmdargs.

• #49, [FreeBSD]: possible memory leak due to missing free() on error condition in getcmdpath().

• #50, [BSD]: fixed getcmdargs() memory fragmentation.

• #55, [Windows]: test_pid_4 was failing on Windows Vista.

• #57: some unit tests were failing on systems where no swap memory is available.

• #58: Process.is_running() is now called before Process.kill() to make sure we are going to kill the correct process.

• #73, [macOS]: virtual memory size reported on includes shared library size.

• #77: NoSuchProcess wasn’t raised on Process.create_time() if Process.kill() was used first.

0.1.2 — 2009-05-06

Enhancements

• #32: add Process.cpu_times().

• #33: add Process.create_time().

• #34: add Process.cpu_percent().

• #38: add Process.memory_info().

• #41: add Process.memory_percent().

• #39: add boot_time().

• #43: Total system virtual memory.

• #46: Total system physical memory.

• #44: Total system used/free virtual and physical memory.

Bug fixes

• #36, [Windows]: NoSuchProcess not raised when accessing timing methods.

• #40, [FreeBSD], [macOS]: fix test_get_cpu_times failures.

• #42, [Windows]: Process.memory_percent() raises AccessDenied.

0.1.1 — 2009-03-06

Enhancements

• #4, [FreeBSD]: support for all functions of psutil.

• #9, [macOS], [Windows]: add Process.uid and Process.gid, returning process UID and GID.

• #11: per-process parent object: Process.parent() property returns a Process object representing the parent process, and Process.ppid() returns the parent PID.

• #12, #15: NoSuchProcess exception now raised when creating an object for a nonexistent process, or when retrieving information about a process that has gone away.

• #21, [Windows]: AccessDenied exception created for raising access denied errors from OSError or WindowsError on individual platforms.

• #26: process_iter() function to iterate over processes as Process objects with a generator.

• Process objects can now also be compared with == operator for equality (PID, name, command line are compared).

Bug fixes

• #16, [Windows]: Special case for “System Idle Process” (PID 0) which otherwise would return an “invalid parameter” exception.

• #17: get_process_list() ignores NoSuchProcess and AccessDenied exceptions during building of the list.

• #22, [Windows]: Process.kill() for PID 0 was failing with an unset exception.

• #23, [Linux], [macOS]: create special case for pid_exists() with PID 0.

• #24, [Windows], [critical]: Process.kill() for PID 0 now raises AccessDenied exception instead of WindowsError.

• #30: psutil.get_pid_list() was returning two 0 PIDs.

0.1.0 — 2009-01-27

Initial release. Supports Linux, Windows, and macOS via per-platform backends (_pslinux, _psmswindows, _psosx) with C extensions for Windows and macOS.

Features

• Process class exposing pid, name, path, and cmdline, with a kill() method.

• get_process_list() returning all running processes.

• ProcessInfo value object passed between the public API and the platform backends.

On this page

• Changelog
  • 8.0.0 (IN DEVELOPMENT)
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  • 0.5.0 — 2012-06-27
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  • 0.4.0 — 2011-10-29
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  • 0.2.0 — 2010-11-13
  • 0.1.3 — 2010-03-02
  • 0.1.2 — 2009-05-06
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  • 0.1.0 — 2009-01-27