Killed all running applications. strace the compiz process. grep the resulting log for DRM_IOCTL system calls:
root@leer-eng:~# for f in `seq 13 24`; do echo `grep DRM_IOCTL strace.log5 | grep 15:50:$f | wc -l` DRM ioctls per second; done
791 DRM ioctls per second
1171 DRM ioctls per second
13816 DRM ioctls per second
11770 DRM ioctls per second
7592 DRM ioctls per second
12990 DRM ioctls per second
8247 DRM ioctls per second
12551 DRM ioctls per second
3133 DRM ioctls per second
2878 DRM ioctls per second
1472 DRM ioctls per second
5 DRM ioctls per second
Up to 12990 system calls per second on system running an idle desktop is insane. This has to be extremely bad for power usage.
ProblemType: Bug
DistroRelease: Ubuntu 16.10
Package: compiz 1:0.9.13.0+16.10.20160818.2-0ubuntu2
ProcVersionSignature: Ubuntu 4.8.0-38.41-generic 4.8.17
Uname: Linux 4.8.0-38-generic x86_64
.tmp.unity_support_test.0:
ApportVersion: 2.20.3-0ubuntu8.2
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Wed Feb 22 10:48:38 2017
DistUpgraded: 2016-10-21 20:02:09,753 DEBUG Running PostInstallScript: './xorg_fix_proprietary.py'
DistroCodename: yakkety
DistroVariant: ubuntu
EcryptfsInUse: Yes
GraphicsCard:
Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06) (prog-if 00 [VGA controller])
Subsystem: Dell 4th Gen Core Processor Integrated Graphics Controller [1028:05be]
GsettingsChanges:
b'org.compiz.core' b'outputs' b"['1366x768+0+0']"
b'org.compiz.core' b'active-plugins' b"['core', 'composite', 'opengl', 'grid', 'vpswitch', 'move', 'mousepoll', 'compiztoolbox', 'copytex', 'snap', 'regex', 'resize', 'imgpng', 'wall', 'commands', 'place', 'session', 'unitymtgrabhandles', 'animation', 'expo', 'workarounds', 'ezoom', 'staticswitcher', 'fade', 'scale', 'unityshell']"
InstallationDate: Installed on 2015-10-27 (483 days ago)
InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
MachineType: Dell Inc. Latitude E6540
PackageArchitecture: all
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.8.0-38-generic root=UUID=d9bb8816-0291-4e8a-b513-6dfc50e0877f ro quiet splash 8250.nr_uarts=4 elevator=noop scsi_mod.use_blk_mq=1 vt.handoff=7
SourcePackage: compiz
UpgradeStatus: Upgraded to yakkety on 2016-10-22 (123 days ago)
dmi.bios.date: 12/01/2015
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A17
dmi.board.name: 0RHT9R
dmi.board.vendor: Dell Inc.
dmi.board.version: A00
dmi.chassis.type: 9
dmi.chassis.vendor: Dell Inc.
dmi.modalias: dmi:bvnDellInc.:bvrA17:bd12/01/2015:svnDellInc.:pnLatitudeE6540:pvr00:rvnDellInc.:rn0RHT9R:rvrA00:cvnDellInc.:ct9:cvr:
dmi.product.name: Latitude E6540
dmi.product.version: 00
dmi.sys.vendor: Dell Inc.
version.compiz: compiz 1:0.9.13.0+16.10.20160818.2-0ubuntu2
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.70-1
version.libgl1-mesa-dri: libgl1-mesa-dri 12.0.3-1ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 12.0.3-1ubuntu2
version.xserver-xorg-core: xserver-xorg-core 2:1.18.4-1ubuntu6.1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.2-1ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160706-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-2
Status changed to 'Confirmed' because the bug affects multiple users.