fbb71f9c0b
QAbstractEventDispatcher blocks and waits constantly on every external event processed; every timer or update from an X or wayland client, mouse move or DRM event. Right now every time this happens we go and check Xwayland for new events, this is a system call (poll) that based on strace will unsurprisingly immediately return with EAGAIN as there's nothing to read from X. If there is something to read our socket notifier will fire. On block we do still need to read any events read in the meantime that weren't dispatched. This cuts down our system calls significantly, which hopefully should have a noticeable impact on performance especially when the kernel is under load. --- Found whilst analysing strace (by accident whilst looking for something else!) In a simple case of xwayland nested running glxgears we go from 28 calls per frame to 21. With many many clients and more input events it'll be an even higher percentage. |
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|---|---|---|
| autotests | ||
| cmake/modules | ||
| data | ||
| doc | ||
| kconf_update | ||
| LICENSES | ||
| po | ||
| src | ||
| tests | ||
| .clang-format | ||
| .gitignore | ||
| .gitlab-ci.yml | ||
| .kde-ci.yml | ||
| CMakeLists.txt | ||
| CONTRIBUTING.md | ||
| KWinDBusInterfaceConfig.cmake.in | ||
| logo.png | ||
| Mainpage.dox | ||
| plasma-kwin_wayland.service.in | ||
| plasma-kwin_x11.service.in | ||
| README.md | ||
KWin
KWin is an easy to use, but flexible, composited Window Manager for Xorg windowing systems (Wayland, X11) on Linux. Its primary usage is in conjunction with a Desktop Shell (e.g. KDE Plasma Desktop). KWin is designed to go out of the way; users should not notice that they use a window manager at all. Nevertheless KWin provides a steep learning curve for advanced features, which are available, if they do not conflict with the primary mission. KWin does not have a dedicated targeted user group, but follows the targeted user group of the Desktop Shell using KWin as it's window manager.
KWin is not...
- a standalone window manager (c.f. openbox, i3) and does not provide any functionality belonging to a Desktop Shell.
- a replacement for window managers designed for use with a specific Desktop Shell (e.g. GNOME Shell)
- a minimalistic window manager
- designed for use without compositing or for X11 network transparency, though both are possible.
Contributing to KWin
Please refer to the contributing document for everything you need to know to get started contributing to KWin.
Contacting KWin development team
- mailing list: kwin@kde.org
- IRC: #kde-kwin on irc.libera.chat
Support
Application Developer
If you are an application developer having questions regarding windowing systems (either X11 or Wayland) please do not hesitate to contact us. Preferable through our mailing list. Ideally subscribe to the mailing list, so that your mail doesn't get stuck in the moderation queue.
End user
Please contact the support channels of your Linux distribution for user support. The KWin development team does not provide end user support.
Reporting bugs
Please use KDE's bugtracker and report for product KWin.
Guidelines for new features
A new Feature can only be added to KWin if:
- it does not violate the primary missions as stated at the start of this document
- it does not introduce instabilities
- it is maintained, that is bugs are fixed in a timely manner (second next minor release) if it is not a corner case.
- it works together with all existing features
- it supports both single and multi screen (xrandr)
- it adds a significant advantage
- it is feature complete, that is supports at least all useful features from competitive implementations
- it is not a special case for a small user group
- it does not increase code complexity significantly
- it does not affect KWin's license (GPLv2+)
All new added features are under probation, that is if any of the non-functional requirements as listed above do not hold true in the next two feature releases, the added feature will be removed again.
The same non functional requirements hold true for any kind of plugins (effects, scripts, etc.). It is suggested to use scripted plugins and distribute them separately.