Comment 7 for bug 1566157

> Any chance that you could track down version when it started to be slow?
> Was composite already slow in previous LTS?

Initial tests show that metacity had about the same performance as marco in 12.04 and in 14.04.
In those versions, `metacity (or marco) --composite` performs only about 60% as well as `metacity --no-composite`,
while `compiz` performs about the same as `metacity --no-composite`.
glxgears example:
no-wm: 394.117
compiz: 393.603
metacity --no-composite: 403.858
metacity --composite: 239.124
marco --no-composite: 404.455
marco --composite: 242.672

Unfortunately in 16.04 it got a whole lot worse, for example:
no-wm: 469.506
compiz: 467.071
metacity --no-composite: 277.188
metacity --composite: 122.936
marco --no-composite: 464.281
marco --composite: 287.314
xcompmgr: 291.990

Now `marco --composite` is still at 60%, while `metacity --composite` is now at only 25% of the optimal performance.
But note that `metacity --no-composite` is also a whole lot worse than `marco --no-composite`.

Alberts do you want me to try with non-LTS releases as well?

These tests were made by running a plain `xinit` (which gives a simple xterm) on top of a usual Ubuntu gnome-flashback installation, while also installing marco there.