gnome-shell uses over 300% CPU most the time

[Paweł Szafer]

Gnome-Shell in Ubuntu 13.10 is using 300-400% CPU most of the time.

I can't track source of the problem.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: gnome-shell 3.8.4-0ubuntu4
Uname: Linux 3.11.0-999-generic x86_64
ApportVersion: 2.12.1-0ubuntu4
Architecture: amd64
Date: Mon Sep 16 12:29:27 2013
DisplayManager: gdm
GsettingsChanges:
 b'org.gnome.desktop.interface' b'clock-show-date' b'true'
 b'org.gnome.desktop.interface' b'clock-show-seconds' b'true'
 b'org.gnome.desktop.interface' b'gtk-im-module' b"'gtk-im-context-simple'"
 b'org.gnome.desktop.interface' b'gtk-theme' b"'MediterraneanLight'"
 b'org.gnome.desktop.interface' b'icon-theme' b"'Humanity'"
InstallationDate: Installed on 2013-09-11 (4 days ago)
InstallationMedia: Ubuntu-GNOME 13.10 "Saucy Salamander" - Alpha amd64 (20130903)
MarkForUpload: True
SourcePackage: gnome-shell
UpgradeStatus: No upgrade log present (probably fresh install)

[Quinn Balazs (qbalazs)]

Nothing in the logs provided has any hints as to why gnome-shell is that much of a resource hog. If you wouldn't mind posting your hardware specs, that would be helpful in any attempts to reproduce the issue. There aren't any leaks as far as I can see in either the mainline or proposed builds of gnome-shell. If you can get a list of specs up by 4PM CST, I will tonight attempt to reproduce the issue.

[Paweł Szafer (pszafer)]

This is Asus notebook N56VZ

http://www.asus.com/Notebooks_Ultrabooks/N56VZ/#specifications

If you need access to my notebook ssh PM me (it will be possible from tomorrow).

[Quinn Balazs (qbalazs)]

The other helpful upload to have would be a valgrind log. Follow the instructions here https://wiki.ubuntu.com/Valgrind. This will detect any memory issues, which as the gnome-session logs didn't show any glaring issues, is what I'm leaning towards calling this. The valgrind log will give me a clearer idea of how to proceed, and I will let you know what the next steps will be. I'll know if it's reproducible for me in about an hour, I'm going to snag a n56vz from IT on my way out of work.

[Paweł Szafer (pszafer)]

My command:
"G_SLICE=always-malloc G_DEBUG=gc-friendly valgrind -v --tool=memcheck --leak-check=full --num-callers=40 --log-file=valgrind.log $(which gnome-shell) --replace"

I attached valgrind.log.

Thanks for help!

[Paweł Szafer (pszafer)]

Hello,
I'm sure this bug is related to Chromium-browser.

When I logged in and using programs like nautilus, gnome takes about 60% CPU, but when chromium is running, then gnome-shell takes >100% CPU and even after closing chromium it doesn't come back to usage in the level of 60% CPU

I don't know if this bug is cause by HW acceleration in chromium, gtk theme problem or something else.

[Paweł Szafer (pszafer)]

As attach chromium-browser valgrind.log
I don't see there anything important, but maybe it will help to investigate bug

[Quinn Balazs (qbalazs)]

Lets rule out memory related issues first. Would you post the output of "free" during one of the times that you are having this problem. It's quite possible that this is due to either SWAP being disabled, or having too small a SWAP partition. I've also done some poking around with different versions of chromium, and in the last few releases, Google Chrome Renderer acts up in combination with flash, and I haven't seen a patch for that particular issue come over here yet. A patch exists, but hasn't come up for consideration in chromium yet as far as I can see. If we can connect this issue to that bug, I will propose integrating the aforementioned patch into the next stable upstream release so that it should get integrated down here as well.

Quinn Balazs

[Paweł Szafer (pszafer)]

Hello, GParted says that linux-swap is enabled.

Below are free outputs. There were four programs opened: byobu, gnome-terminal, chromium-browser (2 tabs) and gnome-shell.

gnome-shell >300% CPU
             total used free shared buffers cached
Mem: 15866272 1764040 14102232 0 77888 768956
-/+ buffers/cache: 917196 14949076
Swap: 15625212 0 15625212

gnome-shell >500%(!) CPU
             total used free shared buffers cached
Mem: 15866272 1919532 13946740 0 89188 803980
-/+ buffers/cache: 1026364 14839908
Swap: 15625212 0 15625212

[Paweł Szafer (pszafer)]

one more free. It's almost an hour gnome-shell takes >300% CPU

             total used free shared buffers cached
Mem: 15866272 5006144 10860128 0 167296 1659168
-/+ buffers/cache: 3179680 12686592
Swap: 15625212 0 15625212

Running programs:
- eclipse,
- virtualbox,
- chromium with 19 cards,
- firefox with 2 cards,
- gnome-terminal.

[Quinn Balazs (qbalazs)]

Okay, I feel now we can safely rule out memory issues as the culprit. With regards to graphics drivers, are you using open source (nouveau), or NVIDIA's proprietary drivers?

[Paweł Szafer (pszafer)]

"Kernel driver in use: i915"

Nvidia driver wasn't stable on my system (I've tried several times to run nvidia drivers, always fail for some reasons).

[Paweł Szafer (pszafer)]

I don't know what happended, but after few lasts updates gnome-shell takes only 100% CPU and from time to time picks up to 300/400% CPU

[Launchpad Janitor (janitor)]

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

[OrlandoSaavedra (orlandosaavedra)]

I'm also experiencing this issue after upgrading from 13.04 to 13.10. System was stable before that
gnome-shell cpu usage goes from 60% to 250% and keeps above 100% usage like 90% of time.

Laptop: Dell Latitude E6410, Intel VGA, 8 GB of memory, Ubuntu gnome (ubuntu-gnome-desktop) 64-bits.

[Paweł Szafer (pszafer)]

After upgrading to kernel-v3.13-rc3 problem gone!

kernel-fixed-upstream-v3.13-rc3

[Daryl Tucker (daryltucker)]

I agree that this issue happens when Chromium is running.

It's still affecting 3.13.0-35-generic (Ubuntu)

[Paweł Szafer (pszafer)]

What's your version of Chromium?

[Stu (stu-axon)]

Same laptop, same problem.

free -h shows 10G free.

Laptop is heating the whole room !

[Daniel van Vugt (vanvugt)]

Thank you for reporting this bug to Ubuntu.
Ubuntu 13.10 (saucy) reached end-of-life on July 17, 2014.

See this document for currently supported Ubuntu releases:
https://wiki.ubuntu.com/Releases

We appreciate that this bug may be old and you might not be interested in discussing it any more. But if you are then please upgrade to the latest Ubuntu version and re-test.

[Launchpad Janitor (janitor)]

[Expired for gnome-shell (Ubuntu) because there has been no activity for 60 days.]