Cinnamon using a lot of CPU

I have a fresh install of Ubuntu 15.10, I installed cinnamon. I observed than the latter was using a lot of CPU, see below:

I see no reason for this, and if I kill the process, cinnamon launches automatically and this behaviour starts again.

I did not activate costly 3D features or whatever in the interface. Any idea how this could be solved?

Specs: PU: Core i7, RAM: 8Gb

2 Answers

Through process of elimination I found some applets can cause this behavior, in my case these two:

• temperature@fevimu (for CPU temp on each core/cumulative)
• (ATI and NVidia cards)

Of the two, the GPU applet appears more impacting. Running the CPU applet for several hours results in occasional window freezes concurrent with CPU spikes.

ALT+F2 - r usually restores Cinnamon to typical CPU (2%-3%) and reduces its RAM utilization by 50MB-75MB upon restart. Seems to indicate some applets which do a lot of frequent polling are not cleaning up after themselves.

About my laptop -

System report generating...

SYS

Linux fender 4.2.0-1-amd64 #1 SMP Debian 4.2.6-1 (2015-11-10) x86_64 GNU/Linux

CPU

model name : Intel(R) Core(TM)2 Duo CPU T9600 @ 2.80GHz model name : Intel(R) Core(TM)2 Duo CPU T9600 @ 2.80GHz

RAM

KiB Mem : 8108740 total, 330984 free, 2361056 used, 5416700 buff/cache

HDD

/dev/sda1 38317204 17780024 18567696 49% / /dev/sda5 81572908 23645824 53760312 31% /home /dev/sdb1 240232960 39382632 188624076 18% /int

GPU

01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] RV635/M86 [Mobility Radeon HD 3650]

GUI

CINNAMON_VERSION=2.6.13

UXE

2.6.13-1 cinnamon 2.6.13-1 cinnamon-common 2.6.0-2 cinnamon-control-center 2.6.0-2 cinnamon-control-center-data 2.6.2 cinnamon-core 2.6.5-1 cinnamon-desktop-data 2.6.2 cinnamon-desktop-environment 2.6.3-1 cinnamon-l10n 2.6.4-2 cinnamon-screensaver 2.6.3-2 cinnamon-session 2.6.3-2 cinnamon-session-common 2.6.3-2 cinnamon-settings-daemon 2.6.5-1 gir1.2-cinnamondesktop-3.0 2.6.0-2 libcinnamon-control-center1:amd64 2.6.5-1 libcinnamon-desktop4:amd64 2.6.0-2 libcinnamon-menu-3-0

I suppose this has different reasons in each case.

In my case, if I start Cinnamon with "software rendering", it has really high CPU usage, similar as in the question above (e.g. around 200%).

If I start it without "software rendering", it is much better (e.g. around 4%).

I suppose that on some systems, if the graphics card is not fully supported or drivers are missing, a similar effect can happen.