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by majewsky 3127 days ago
(Nitpick: Traditional WMs composite as well, they just do it on the CPU instead of the GPU.)

That's interesting. I remember the developer of KWin (KDE's window manager) saying that he considered disabling GPU compositing when the battery runs low, but he couldn't prove that this actually saves energy. In fact, on some configurations, GPU compositing was less power-intensive than CPU compositing.
1 comments
aidenn0 3127 days ago
I thought traditional WMs had the clients send the draw commands directly to the server, rather than doing any compositing themselves?

It's definitely true that different GPUs have different power profiles (and even the same GPU with different drivers).

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majewsky 3127 days ago
No Qt or GTK application sends draw commands to the X server anymore (except for the final "draw window-sized pixmap"). That only applies to xterm or maybe Tcl/Tk stuff.
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aidenn0 3127 days ago
This still isn't compositing. If I have 10 windows all with the same X/Y coordinates, the only window sending any draw commands at all is the top window with a traditional wm.
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infogulch 3127 days ago
Don't forget "race to sleep". If the GPU takes 3x more power but completes 10x faster and can go back into low power mode sooner that could be another power savings.
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