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[Laurent Gauthier <mr.l.gauthier@xxxxxxxxx>]

This issue has been killing the battery of my laptop with 15.04 install.

Not only is compiz using way more CPU than it should, but it also
causing Xorg to undergo a lot of activity totalling more than 100% of a
CPU core on my Core i5 laptop. Needless to say that battery life was
disastrous.

Now after a little time spent researching this I found a work-around
that appears to work:

1. Install the "Compiz config settings manager"
2. Under the OpenGL section in this settings manager, uncheck the "Sync to VBlank" option
3. Log out
4. Log in

And the problem appears to be gone.

After being over 60% CPU at all times compiz is now consistently under
1% CPU. The same goes for Xorg.

-- 
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to compiz in Ubuntu.
https://bugs.launchpad.net/bugs/1293384

Title:
  Compiz CPU usage dramatically increased in Ubuntu 14.04

Status in Compiz:
  Triaged
Status in compiz package in Ubuntu:
  Triaged

Bug description:
  It appears that the workload of low-level graphical operations used by
  compiz when, for example, moving windows has increased dramatically
  between Ubuntu 12.04 and Ubuntu 14.04.

  This might not be that visible when using high-end gpus, but should be
  clearly visible when using compiz on llvmpipe and to some-extent
  invalidates the approach of using compiz on top of llvmpipe as a
  fallback when no GPU is available:

  How to reproduce:
  1) Use the unity-3d desktop in Ubuntu 14.04 on top of a non-accelerating Xorg driver like "modesetting". Move windows around. Note peak and average cpu-usage.

  How to verify compiz is the culprit:
  1) copy /usr/bin/compiz from a Ubuntu 12.04 installation. Drop it in as /usr/bin/compiz on 14.04. Reboot. Perform the same window movement. CPU-usage should be substantially lower.

  This problem also affects VMs running on VMware ESX with a software-
  rendering GPU. Window movement becomes sluggish, which suggests that
  even with GPUs, compiz has increased the number of operations required
  to move windows.

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