| Summary: | Poor performance when open a more than N argb windows | ||
|---|---|---|---|
| Product: | [Plasma] kwin | Reporter: | zvova7890 |
| Component: | performance | Assignee: | KWin default assignee <kwin-bugs-null> |
| Status: | RESOLVED FIXED | ||
| Severity: | normal | CC: | kishore96, nate, tromzy, xaver.hugl |
| Priority: | NOR | Flags: | mgraesslin:
Wayland+
mgraesslin: X11+ |
| Version First Reported In: | 5.15.90 | ||
| Target Milestone: | --- | ||
| Platform: | Other | ||
| OS: | Linux | ||
| Latest Commit: | Version Fixed In: | 6.1 | |
| Sentry Crash Report: | |||
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Description
zvova7890
2019-05-24 19:16:19 UTC
I also noticed that while kwin_wayland is snappier and smoother than kwin_x11 on an empty session (or with few windows), performance degrades fast when multiple windows are open. Interest thing. I had received updates for my archlinux, with released kwin(5.16) and Qt 5.13(before I'm used beta releases), and have tested this again. In x11 if open 50 konsole instances - performance regress to, but if disable composition all becomes fine. Second my test continue in weston compositor. I'm run 150 instances weston-terminal and all continue work smooth, but if in wayland mode run some konsole in 150 instances - performance is regress. Then I'm install gnome-terminal and also run with 150 instance - same result as with konsole. What is this and why weston "native" applications work better with more instances - I don't know. Maybe weston applications used more proper way for rendering invisible areas of application, I don't know. These are my observations, if it could somehow help Maybe it's a problem with translucent windows? Especially if window background is blurred a performance degrading is to be expected with more open windows. It is default kde theme, transparent and blured only plasma(taskbar what visible). Window is not transparent, only when moved. But I had disabled transparency and blur in effect settings - and window run more smoother. Wait... it's could be window shadows, that are transparent and blured. But in case X11 when I disabled transparent and blur effects window run smoother in a lot instances, in wayland session it's not affected and performance continues in low level. Another interest thing - if open ksysguard in 100+ instances, all fine. But with konsole slideshow O_o. This is on x11, on wayland stable performance problem with any windows. I tried to switch to wayland by default, but when I make some my work and open 10+ windows lags can't make me productive. I had switched back to x11 Shadows are translucent and Konsole is translucent. That sounds a lot like an issue in our translucent windows rendering path. Looks like. ksysguard in many instances work fine with shadows(normal size in shadow settings) in x11, in wayland much slower. So there is 2 problems: 1. konsole in anywhere slow with many instances because translucent is flagged in all cases and also in case when translucent and blur is disabled in konsole profile. 2. Wayland kwin backend has some problems with rendering translucent windows. But not sure, because with disabled shadows with many instances of ksysguard is also faced slow rendering Iirc Qt on Wayland uses an alpha channel by default, so we are always in the "Konsole" Case. If Qt doesn't inform Wayland of opaque surfaces, that sure would be worth a bug report. (In reply to Christoph Feck from comment #9) > If Qt doesn't inform Wayland of opaque surfaces, that sure would be worth a > bug report. Yes and no. I would say it was a bug on X11 that argb was not supported out of the box. And anyway any gtk application is argb due to csd. We need to become better in rendering argb windows. > any gtk application is argb due to csd
I am pretty sure GTK informs wayland about the opaque region _inside_ the window. Otherwise a stack of windows always needs to be composited completely from back to front.
I had installed gnome, run under wayland, and create 50 windows od gedit(and then gnome-terminal) - performance is ok. Then i make 50 windows of ksysguard(uses wayland mode) - faced slow rendering, with konsole same situation. So: 1. GTK applications correct informs gnome compositor about opaque surfaces. 2. KDE/Qt applications always in transclucent mode. 3. GTK applications is always in transclucent mode under kwin compisition. Maybe kwin-wayland doesn't uses opaque flag and always goes to the transclucent composition for all window? And second problem - that the Qt applications nothing inform about opaque surfaces, and compositors take default value as opaque = true. Any ideas/progress with this? Still having this issue( I’m really want to switch my session on wayland and continue deep testing, but I cannot, because I’m using more than 5 window, xorg session still more smooth I had built latest for now kwin from git and related kwayland* packages, seems situation for now is match better! Also firefox now not laggy when hide/show action is performed. Maybe that related to https://invent.kde.org/plasma/kwin/-/commit/11c7e7a64da3b39c89a1392f1f1112bc8c8ea8b7 commit. I'm waiting for release for full true test Bug is still here :( konsole windows count in direct ratio affect performance. Over 20 windows of konsole become desktop to slideshow. Also, when desktop has not windows showed, all slideup plasma menus shows smoothly, but if open at least one window - smooth is disapearing. When you are working and open many windows - interface reaction is slowing down. X11 session doesn't have this effect. You can open as much as you want windows and this doesn't affect to the interface FPS. Feels like some compositor problems. Can you still reproduce this issue in Plasma 6? Yes, I do. But I want to test it on 6.1 with the triple buffering feature. Will test this weekend With triple buffering and https://invent.kde.org/plasma/kwin/-/merge_requests/5779 the issue seems to be resolved. At least it is now have performance parity between Wayland and X11 session. So, this bug can be considered resolved. Thanks! Great news! |