why compiz performance on XGL is smoother?

[delphinen]

I have Arch with latest nvidia drivers and Compiz, running with --use-cow and --indirect-rendering. No XGL/AIGLX. The rendering is very good, specially in browsers. I can play games without problem. Everything runs almost perfect.

On the other side, I have Ubuntu with XGL and latest Compiz-Quinn before it become Beryl. Window movement is much smoother, the difference is obvious; but the rendering of the apps is not so fast, specially in browsers. I cant play games directly on top of Compiz.

So, I would like to know, why Compiz its much smoother on XGL? its because XGL "priorizes" the rendering of the windows itself?

[stalynx]

try this

export __GL_YIELD="NOTHING"; compiz --replace --use-cow gconf

when you launch compiz with Nvidia, for me XGL and Nvidia performance are about the same.

[RYX]

The smoother performance is because Xgl is just faster than aiglx/nvidia. That is related to the different architectures of Xgl/aiglx. Check this: How Xgl works (http://principe.homelinux.net/)

:)

[delphinen]

export __GL_YIELD="NOTHING"; compiz --replace --use-cow gconf

I tried that. Maybe its a little smoother, but still, not totally smooth like XGL. I dont know, maybe its some refresh-rate thing, but that would be strange.

The smoother performance is because Xgl is just faster than aiglx/nvidia. That is related to the different architectures of Xgl/aiglx.

Yup, I supposed that could be the reason, but I didnt read anyone specifically saying "XGL its smoother" yet

[mikedee]

You might want to look at the settings on each one, particularly in wobble.

There are quite a few performance options which can make it run faster. If you are using the latest compiz-quinn then it will use csm for the settings whilst compiz uses gconf.

[RYX]

I think the "smoother" look is because nvidia/aiglx use indirect rendering where xgl uses direct rendering ... and rendering directly to the hardware is faster than having a layer (the X-server) between app and hardware ... (I know this is a bad explanation).

:)