UI freeze for up to 10sec when maximizing window

[Steve Magoun]

Maximizing a terminal window often takes up to 10 seconds on my system. During this time the mouse cursor can move but the UI is otherwise unresponsive.

To reproduce:
1) Launch a terminal window, e.g. via Ctrl-Alt-T
2) Click the maximize button in the terminal window

Expected results:
Terminal window does fullscreen instantly

Actual results:
Terminal window stays at the original size for up to 10 seconds. During this time no UI elements work (can't switch to a new window, the launcher is unresponsive, etc). The terminal window is eventually drawn full-screen.

This is reproducible about 75% of the time I try to maximize a terminal window. I haven't seen the problem affect windows in other applications. If maximizing a window does not produce the delay, un-maximizing it then re-maximizing it often causes the delay to appear.

This is a recent regression - I believe the freeze/delay was not present in Unity 6.8.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: unity 6.8.0-0ubuntu2
ProcVersionSignature: Ubuntu 3.5.0-17.28-generic 3.5.5
Uname: Linux 3.5.0-17-generic x86_64
NonfreeKernelModules: nvidia
.proc.driver.nvidia.gpus.0: Error: [Errno 21] Is a directory: '/proc/driver/nvidia/gpus/0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 304.43 Sun Aug 19 20:14:03 PDT 2012
 GCC version: gcc version 4.7.2 (Ubuntu/Linaro 4.7.2-2ubuntu1)
.proc.driver.nvidia.warnings.fbdev:
 Your system is not currently configured to drive a VGA console
 on the primary VGA device. The NVIDIA Linux graphics driver
 requires the use of a text-mode VGA console. Use of other console
 drivers including, but not limited to, vesafb, may result in
 corruption and stability problems, and is not supported.
.tmp.unity.support.test.0:

ApportVersion: 2.6.1-0ubuntu3
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
Date: Mon Oct 22 10:01:45 2012
DistUpgraded: 2012-08-07 11:19:37,876 DEBUG enabling apt cron job
DistributionChannelDescriptor: canonical-oem-foo-12345
DistroCodename: quantal
DistroVariant: ubuntu
DkmsStatus:
 nvidia-current, 304.43, 3.5.0-17-generic, x86_64: installed
 virtualbox, 4.1.18, 3.5.0-14-generic, x86_64: installed
 virtualbox, 4.1.18, 3.5.0-15-generic, x86_64: installed
 virtualbox, 4.1.18, 3.5.0-16-generic, x86_64: installed
 virtualbox, 4.1.18, 3.5.0-17-generic, x86_64: installed
GraphicsCard:
 NVIDIA Corporation G84 [GeForce 8600M GT] [10de:0407] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Apple Inc. Device [106b:00a0]
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Beta amd64 (20100901.1)
JockeyStatus:
 kmod:nvidia_current_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)
 kmod:nvidia_experimental_304 - Experimental NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)
 kmod:nvidia_current - nvidia_current (Proprietary, Enabled, Not in use)
 kmod:nvidia_173_updates - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)
 kmod:nvidia_173 - NVIDIA binary Xorg driver, kernel module and VDPAU library (Proprietary, Disabled, Not in use)
MachineType: Apple Inc. MacBookPro3,1
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.5.0-17-generic root=UUID=4b3d81ed-fb5d-4946-97c0-ec537e1bfa3f ro quiet splash
SourcePackage: unity
UpgradeStatus: Upgraded to quantal on 2012-08-07 (75 days ago)
dmi.bios.date: 03/05/08
dmi.bios.vendor: Apple Inc.
dmi.bios.version: MBP31.88Z.0070.B07.0803051658
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: Mac-F4238BC8
dmi.board.vendor: Apple Inc.
dmi.board.version: PVT
dmi.chassis.asset.tag: Asset Tag#
dmi.chassis.type: 2
dmi.chassis.vendor: Apple Inc.
dmi.chassis.version: Mac-F4238BC8
dmi.modalias: dmi:bvnAppleInc.:bvrMBP31.88Z.0070.B07.0803051658:bd03/05/08:svnAppleInc.:pnMacBookPro3,1:pvr1.0:rvnAppleInc.:rnMac-F4238BC8:rvrPVT:cvnAppleInc.:ct2:cvrMac-F4238BC8:
dmi.product.name: MacBookPro3,1
dmi.product.version: 1.0
dmi.sys.vendor: Apple Inc.
version.compiz: compiz 1:0.9.8.4-0ubuntu3
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.39-0ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.0-0ubuntu1
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.0-0ubuntu1
version.nvidia-graphics-drivers: nvidia-graphics-drivers N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.13.0-0ubuntu6
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.99.99~git20120913.8637f772-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.20.9-0ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.2-0ubuntu3

[Steve Magoun (smagoun)]

I sampled a few call stacks of the slowdown using gdb. It looks like the system is spending a lot of time in the NVIDIA driver, called from libpixman-1-0's fetch_and_convert_pixel. I've attached a representative stack trace from GDB, with pixman debug symbols.

[Steve Magoun (smagoun)]

Re: comment #2, I sampled the xorg process - not the terminal or unity. 'top' showed that all of the CPU time was being spend in xorg.

[Launchpad Janitor (janitor)]

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

[dino99 (9d9)]

That version is no more supported; please open a new bug report if the actual archive found version also has the same issue.