Ubuntu 12.10 has been released and you may have already started
customizing it. Below is a small tweak that will make Unity dash more
responsive.
Ubuntu 12.10 has a 'low graphics mode' that disables some dash and
launcher effects like active blur and transparency. It also darkens dash
for improved visibility. By sacrificing these effects, you can improve
Unity performance.
This low graphics mode is enabled by default in llvmpipe software mode
which is used as a fallback method if your system doesn't support 3D
hardware acceleration. However, on high end systems, you can enable low
graphics mode without getting into fallback renderer.
Low graphics mode can be enabled by adding following line to
~/.xprofile (if the file doesn't exist, create it)
export UNITY_LOW_GFX_MODE=1
Logout, and come back for the effect to take place.
To check if you are running llvmpipe software mode or not, run the following command:
glxgears -info
In software mode, you will get output like this:
GL_RENDERER = Gallium 0.4 on llvmpipe (LLVM 3.1, 128 bits)
GL_VERSION = 2.1 Mesa 9.1-devel
GL_VENDOR = VMware, Inc.
Low graphics mode changes are mostly same as disabling blur and
transparency effects through compiz config settings manager (CCSM). You
can use either of these methods to improve Unity performance on
your desktop.