compiz high CPU usage when screen powered off

[James Page]

When my screen powers off after 5 minutes of inactivity compiz starts consuming a large amount of CPU time (resulting in fans running harder - hence I noticed the issue).

Stops as soon as I unlock - output from top indicates compiz is consuming alot of CPU time:

top - 18:29:13 up 10:12, 0 users, load average: 0.19, 0.39, 0.75
Tasks: 242 total, 1 running, 239 sleeping, 0 stopped, 2 zombie
Cpu(s): 4.5%us, 2.0%sy, 0.0%ni, 93.3%id, 0.3%wa, 0.0%hi, 0.0%si, 0.0%st
Mem: 3980564k total, 3223868k used, 756696k free, 177728k buffers
Swap: 4124668k total, 0k used, 4124668k free, 1084480k cached

  PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
13031 jamespag 20 0 1519m 105m 52m S 26 2.7 323:22.61 compiz 12796 root 20 0 568m 181m 141m S 9 4.7 4:35.38 Xorg
13469 jamespag 20 0 981m 277m 45m S 3 7.1 3:35.75 firefox 13095 jamespag 20 0 397m 11m 7584 S 2 0.3 0:02.18 bamfdaemon
13797 jamespag 20 0 645m 38m 18m S 2 1.0 0:17.97 /usr/bin/termin 13006 jamespag 20 0 27948 3488 628 S 1 0.1 0:04.06 dbus-daemon

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: compiz 1:0.9.7.2-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-20.32-generic 3.2.12
Uname: Linux 3.2.0-20-generic x86_64
NonfreeKernelModules: fglrx
.tmp.unity.support.test.0:

ApportVersion: 1.95-0ubuntu1
Architecture: amd64
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
CompositorRunning: compiz
Date: Sat Mar 24 18:25:21 2012
DistUpgraded: Fresh install
DistroCodename: precise
DistroVariant: ubuntu
DkmsStatus:
 blcr, 0.8.2: added
 fglrx, 8.960, 3.2.0-20-generic, x86_64: installed
MachineType: Dell Inc. Studio 1558
PackageArchitecture: all
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-20-generic root=UUID=c3b984e3-15cf-4a8c-a718-868679884017 ro
SourcePackage: compiz
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 06/24/2010
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A07
dmi.board.name: 0874P6
dmi.board.vendor: Dell Inc.
dmi.board.version: A07
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: A07
dmi.modalias: dmi:bvnDellInc.:bvrA07:bd06/24/2010:svnDellInc.:pnStudio1558:pvrA07:rvnDellInc.:rn0874P6:rvrA07:cvnDellInc.:ct8:cvrA07:
dmi.product.name: Studio 1558
dmi.product.version: A07
dmi.sys.vendor: Dell Inc.
version.compiz: compiz 1:0.9.7.2-0ubuntu1
version.fglrx-installer: fglrx-installer N/A
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.32-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 8.0.2-0ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 8.0.2-0ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.11.4-0ubuntu7
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.0-0ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20111219.aacbd629-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.17.0-1ubuntu4
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20111201+b5534a1-1build2

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[James Page (james-page)]

I recently switched from using the fglrx driver to using the open-source radeon driver and this issue appears to have gone away.