kwin-4.7.1-0ubuntu2~ppa1 needs testing

Clay Weber claydoh at
Tue Sep 13 12:34:41 UTC 2011

On Tuesday, September 13, 2011 02:02:01 PM Harald Sitter wrote:
> On Tue, Sep 13, 2011 at 1:47 PM, Dan Chen <seven.steps at> wrote:
> > On Sep 12, 2011 11:31 PM, "Clay Weber" <claydoh at> wrote:
> >> What sort of things should we be looking for,  positive or negative?
> > 
> > Ditto. I normally have several dozen app/windows open, and the
> > performance hitches I noticed before seem resolved. It would be nice to
> > know which parameters to test, however.
> From Martin's top secret mail:
> > During working for an optimization in 4.8 we noticed that we do deep
> > non-const vector copies where a const at() operation was expected. This
> > means that we have in each frame: 4x+5xy unneeded copy operations
> > (x == number of loaded effects)
> > (y == number of windows).
> So on a stock kubuntu desktop we have something like 15 effects
> activated, additionally say you have a browser, a music player and a
> chat window (mind you, plasma is also a window ;)) that means per
> frame you get 4*15+5*4=80 copies of effects, if you get 15 frames per
> second (which would be mostly enough to perceive the desktop as
> responsive) that means 15*80=1200 copies. You probably do not have 15
> but >40 frames per second that means 3200 copies. Now I actually
> forgot what I wanted to write about...
> Ah right, so, if you turn on *all* kwin effects (or at least those
> that load on your system) and open as many windows a possible, kwin
> should not feel overly sluggish (movement of windows, resizing etc.).
> Also all effects that worked with the old package should still work
> with the new one.
In that case, it is all working well then :D No sluggishness here.
Clay Weber 

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