Nemo is always at 20% CPU and hard disk is never idle

[Anush Ramani]

Version: Linux Mint 17, Cinnamon 64-bit

System model: Lenovo T520

What you did for the problem to happen: I upgraded (fresh install) from Mint 15 to 17 a few days back

What happened: The nemo process appears to always be at 20% CPU usage and my hard disk is constantly "working" (HDD light keeps flashing and I can hear it). If I kill the nemo process, the HDD immediately goes quiet. If I open up nemo again (by using the file manager), it's back to 20% CPU and a constantly working HDD.

If the problem happened once, sometimes, or always: Always

Screenshot of top attached. Not sure what other technical details I can include, but happy to provide if requested.

[Jean-Francois Moulin (jean-francois-moulin-b)]

I confirm the problem on my lenovo t440p. (Linux Mint 17, Cinnamon 64-bit)
As soon as Cinnamon is active, a nemo process runs with 100% of one of the cores. I did not check the disk activity.
Tried to kill process and restart it, same behaviour.

[Jean-Francois Moulin (jean-francois-moulin-b)]

Seems we are not the only ones to suffer of this problem:
https://ask.fedoraproject.org/en/question/49871/why-does-nemo-eats-up-so-much-cpu-whole-core-on-idle/
This thread suggests a possible problem with cinnamon 2D, but this is not what I am running.

[Josh Ventura (joshv10)]

Also affects Xubuntu 14.04 (Trusty).

3.13.0-49-generic #83-Ubuntu SMP Fri Apr 10 20:11:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

Problem *seems* to be a failure to generate thumbnail images, or perhaps that is instead a symptom. My guess is that it continually tries and fails to generate preview thumbnails for some reason. It may be to do with my having symlinked the folder it's trying to use to another (larger, non-SSD) drive. Leaving Nemo to its business, it will never successfully generate a thumbnail for any image or video, but Nautilus and Thunar have no trouble.

[bbruecker (bb-benjaminbruecker)]

I have high CPU (~80%) usage with nemo on 17.3 on a FAT32 drive. Sometimes the folders are not displayed or it takes several minutes to display them. To disable the creation of previews does not have any effect. I don't have this issue with the same data on different on NTFS and EXFAT formated drives nor by Nautilus with the FAT32 drive.

[Stefano Silvestrini (stefano-silvestrini78)]

Hi all,
I had the same issue with nemo 3.2.2 on Mint 18.1. I've find out (strace nemo "path to the folder which generate my problem") that I had a bookmark pointing to a sub-folder which no longer exists.
Bookmark deleted, problem disappeared.

[John McDougall (sysadmin-mcdougallshome)]

I am using nemo on ubuntu 16.04 as default file manager. Nemo ran up cpu usage to 20% and tied up more than 1GB memory. The disk was always active. I noticed that I had a small jpg file that had the clock symbol on it like it was waiting to do something. I copied the file to a new one and deleted the old one and the problem instantly disappeared. It apparently was having some sort of problem generating a thumbnail image. It is strange that this problem has apparently been going on for years and it is unassigned.