> Probably way easier is to document, to execute in terminal: > gsettings set org.gnome.metacity compositing-manager false
It's easy for one sysadmin to run a few commands in a terminal. It's not easy for hundreds of students, e.g. 5-10 years old, to run a few commands in a terminal. Sysadmins (or packagers) can provide a system-wide override with /usr/share/glib-2.0/schemas/20_metacity.override but that will only work with new users. They can provide overrides for all users with mandatory gsettings. But the /usr/local/bin/metacity wrapper can have logic to active or deactivate compositing per user, or per machine, based on the CPU, the graphics card etc etc, and it's very easy to integrate it with LTSP. Anyway that part isn't important; the most important thing is if the non-compositing case will be a supported use case in Ubuntu gnome-flashback 16.04 or not. I'll do some more benchmarks with gnome-flashback and with other DEs like Mate/XFCE/LXDE. Thank you guys! -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to metacity in Ubuntu. https://bugs.launchpad.net/bugs/1565640 Title: Set compositing-manager=false by default Status in metacity package in Ubuntu: Won't Fix Bug description: In Ubuntu 12.04 and 14.04, metacity's compositing-manager was false by default. In 16.04, it's been set to true. I tried to pinpoint the advantages vs the disadvantages of that, and currently I've only seen disadvantages. I was testing with: gsettings set org.gnome.metacity compositing-manager false (or metacity --no-composite) versus: gsettings set org.gnome.metacity compositing-manager true (or metacity --composite) Speed: the speed for window drawing and moving around is 3-5 times slower when compositing is enabled. This is rather visible locally on old computers, but it becomes a real problem when Xorg is used over the network, like for example in LTSP thin clients. There, dragging around a window draws it in slow motion a whole lot behind the mouse, like a trail, while with compositing disabled, everything is lightning fast. RAM: xrestop shows that with a couple of windows open, metacity now needs 10 MB more RAM. This value increases with the number of open windows. Vsync: in most cases vsync was broken with or without compositing (while with compiz it's working much better). I tried with youtube videos, with VLC etc. The only difference I saw is that with some SDL games like teeworlds, vsync was working with compositing disabled, and was broken with compositing enabled. So my personal results is that metacity's compositing-manager=true doesn't have any advantage currently, and that it makes old client and LTSP client performance a whole lot worse. And unfortunately those are exactly the cases where we prefer gnome-session-flashback instead of e.g. Unity. Therefore I'd like to ask you to consider disabling it by default like it was in the past. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/metacity/+bug/1565640/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
