How to improve performance of VirtualBox when UNITY_LOW_GFX_MODE is not working?

Especially on a low end machine such as mine (Athlon dual core, GForce 210) running Ubuntu with Unity and Compiz enabled is quite a challenge and may result in a rather slow and sluggish experience.

Virtual machine settings

To improve this I gave the following settings to the virtual machine:

enable VT-x/AMD-V, Nested Paging
2 CPU (from dual core host) with an execution cap at 90% to ensure host operability
2048 Base Memory

256 MB Video Memory

  VBoxManage modifyvm "Name of VM" --vram 256

3D Acceleration enabled
Guest Additions installed

Remove desktop effects

Then I observed a very slow animation for windows and menus. This animations did more harm than use in my virtual machine. Below is three methods how to disable them to get a smoother experience in Virtual Box:

Disable animations with Unity Tweak Tool or Gnome Tweak Tool

With both tools we can disable desktop animations:

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GNOME tweak tool

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Unity tweak tool

Compiz Config Settings Manager

As this is a virtual machine with the option to make a snapshot before you do harmful things to your OS you may probably safely runs ccsm to disable Compiz effects:

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Do not disable windows decoration above

Dconf Editor

Lastly here is how to do it with dconf-editor:

Browse to org.compiz.profiles.default.core and remove the following from active profiles:
```
  'animations' 'fade'
```
Browse to org.compiz.profiles.unity.core and remove the following from active profiles:
```
  'animations'
```

Unfortunately I have found no way to disable the Dash animation, which still will be rather slow.

GNOME Session Flashback

In the likely case you are still not happy with the overall speed of the desktop you may consider installing the GNOME Session Flashback, which will let you log into GNOME Flashback (Compiz or Metacity) with a lean and fast desktop reminiscent of 10.04, but with all the upgraded applications, and the recent kernel:

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