Nemo desktop high CPU usage

[Obadah-H]

 * Nemo version: 4.4.2
 * nemo-desktop has high cpu usage
 * Distribution: Mint 19.3 - 64 bit
 * CPU: i5-6200U, GPU: AMD Radeon R5 M330

Issue

nemo-desktop shows high CPU usage (90%) when doing tasks related to desktop: show desktop, create a file, delete, rename.. etc. Having a clean desktop with no files at all doesn't help.

Other information

• I noticed this problem years ago (since Mint 18)
• Reinstalling the system doesn't help
• Killing nemo-desktop stops high cpu usage once showing desktop (ctrl+D) (in that case, no desktop icons are visible, only wallpaper + conky)
• Didn't check the problem on other PC's
• High CPU usage stops in ~5 seconds
• Changing the kernel (4.5.* / 5.3.*) doesn't help
  

[icarter09]

@Obadah-H are there any specific steps required to reproduce this? I tried renaming several files and deleting files, but the CPU usage never went beyond 15%.

[Obadah-H]

@eli-schwartz As I said, in my case it happens even on a clean installation. I'm using conky to monitor the CPU usage (I think that it's irrelevant).

[eli-schwartz]

I was trying to figure out why I got pinged for a Mint issue... Did GitHub auto complete the wrong user or what?

[leigh123linux]

@Obadah-H
I believe it's conky causing the extra load with it's continuous refreshes, can you reproduce the high load without it?

[Obadah-H]

@icarter09 Yes, I don't know why!

[Obadah-H]

@Obadah-H
I believe it's conky causing the extra load with it's continuous refreshes, can you reproduce the high load without it?

Yep it's conky, case closed!

[kevinnls]

i'm noticing high usage even without Conky :/
hits as much as 27% 32% CPU usage!

Pop!_OS 20.04 (based on Ubuntu 20.04)
Linux kernel: 5.4.0-7642-generic
GNOME version: 3.36.3
gnome-shell version: 3.36.4 (? is that okay?)
X11 windowing system

should i open a separate issue?

PS: honestly no idea what info i should be giving for a query like this so i just threw it all out there

[Obadah-H]

I removed conky and thought that the problem was resolved, but the next day I got the same issue again. It's not a "conky" problem. It's a bug. I even reinstalled Mint all over again, but the problem persists. I changed my machine shortly after I created this thread, and the problem doesn't exists on my new machine.

[Obadah-H]

It's worth to mention that I KNEW that it was the desktop app (not the desktop environment), because in Cinnamon, the desktop has it's own process, and killing it removes the desktop (no more icons on desktop - everything else works). In my case, after killing the process, the CPU usage goes back to normal. So, I was working without the desktop process for a while, till I changed my machine.

[kevinnls]

it is the nemo-desktop app for me too. but surprisingly after i reduced the number of visible files by dumping them all into a folder, the CPU usage seems a lot less for nemo-desktop. but it still has occasional spikes. i'm using gnome-system-monitor to watch the usage btw. any thoughts on this?

[kevinnls]

confirmed!
had 7 visible files in ~/Desktop and CPU usage was 0% with occasional spikes

for i in {0..100}; do touch $i; done

and the CPU usage jumped high and stayed at the ranged of 14% - 33%
can anyone try replicating?

[blueray453]

Using nemo-desktop 5.6.5 in debian sid (gnome).

The autostart file (~/.config/autostart/nemo-desktop.desktop) looks like:

[Desktop Entry]
Type=Application
Name=Nemo Desktop
Comment=Start Nemo desktop at log in
Exec=nemo-desktop
X-GNOME-AutoRestart=true
NoDisplay=true

I have the dconf gsettings set org.nemo.desktop ignored-desktop-handlers "['conky','nemo','nemo-desktop', 'nautilus', 'nautilus-desktop']".

In system monitor, the gnome-desktop memory usage start with ~30MB. Even if do not do anything, the memory usage continue to climb. At some point it reaches 3.5GB and then the desktop become almost unusable.

[mattlach]

Figured I'd chime in.

Not sure if it is the same issue, but I'm seeing 85+% CPU usage (on one core) on a Threadripper 3960x by just copying a 64GB file (large so it takes a while so I can monitor impact) from my home folder to a mounted NFS folder.

• The folder is mounted via fstab (not via nemo)
• Network speed is 10gbit, so transfer is occurring at ~1100MB/s
• CPU usage is being monitored using htop in a terminal window
• htop reports nemo as the process with the high CPU util (not NFS, or anything related to networking)

It seems like file copy activity is resulting in high CPU usage in Nemo, at least with high speed devices.

I did a follow up test copying a file from one NVMe drive to another, and again, HTOP reports nemo with 90+ % CPU usage on one core.

It seems like file copy operations are CPU limited, which really sounds weird to me.

At first I thought this was a nemo issue as well, but I just did a follow up test with cp from the command line, and it is even worse, pegging a single CPU core at 100%.

So, maybe it is not nemo, but something in the NVMe driver or something like that that is amiss? Because I can't imagine that this is normal intended behavior. Copying a file shouldn't be pegging a single core, making file copies CPU limited.

For what it is worth, htop reports the CPU use in red, which means "kernel time".

$ uname -a
Linux matt-desktop 6.5.0-14-generic #14~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Mon Nov 20 18:15:30 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

$ cat /etc/lsb-release
DISTRIB_ID=LinuxMint
DISTRIB_RELEASE=21.2
DISTRIB_CODENAME=victoria
DISTRIB_DESCRIPTION="Linux Mint 21.2 Victoria"

Seems like this may just be the current state of linux though. At least judging by this article:
https://lwn.net/Articles/789623/