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While searching for methods to optimize my KDE4 installation on Ubuntu 10.04 LTS , someone suggests the raster graphics system instead of the default.

Change the default paramter in startkde4 script to plasma-desktop -graphicssystem raster

I've totally no idea what's better and the current one using on my system. How should i find it out , and compare them ? (I'm not using ATI's driver for now , is that XV or opengl ? )

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up vote 1 down vote accepted

From the Kubuntu Forums (A Lighter, Faster (?) Plasma):

There could be problems with the KDE4 installation on Ubuntu 10.04 LTS.

With the older KDE/Qt:

  • Could increase the RAM consumption.
  • Can cause "havoc" with the intel drivers.
  • There were some issues with plasma-netbook, kwin and rekonq.
  • Openoffice won't start unless you set QT_GRAPHICSSYSTEM=native.

With the Kubuntu Oneiric (11.10) the raster system is the default.

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A quick search gave me this:

Running kde4 on slower machines can be helped by a trick which comes with qt4. This is the ability to choose a different method to render things. in general every application which uses qt4 toolkit comes with an option: "--graphicssystem" It's parameter can be: native, raster and opengl. The faster is opengl, but it is very buggy and it's like to corrupt kde icon cache sometimes, the default one is native, slower than raster, but has good performance over network (freenx, ssh -Y benefits from it) , that's the reason because kde devs choose to use it. Raster is slower than opengl, but stable, and faster than native on localhost; other drawbacks of raster graphics system is that it doesn't seems to support subpixel AA very well (if not at all, can't say for sure).

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