Warning [Thread (pooled)]: CoverArt - loadImage 2 cover does not exist: "/mnt/audio/in/album-artist.jpg"
I get the log spammed with many thousand messages like that, and usually it's one cover image that Mixxx complains about, but not always the same.
After a while this blocks the CPU that much that I got massive xruns and had to restart Mixxx to get it usable again.
There are no other irregularities in the log.
Ubuntu Studio 20.04
compiled master with cmake
Debug [Main]: "Mixxx" "2.4.0-alpha-pre" "(git HEAD r7377; built on: May 16 2020 @ 17:13:30)" is starting...
Debug [Main]: Compile time library versions:
Debug [Main]: Qt: 5.12.8
Debug [Main]: libshout: 2.4.1
Debug [Main]: PortAudio: 1246720 PortAudio V19.6.0-devel, revision 396fe4b6699ae929d3a685b3ef8a7e97396139a4
Debug [Main]: RubberBand: 1.8.2
Debug [Main]: SoundTouch: 2.1.1
Debug [Main]: TagLib: 1.11.1
Debug [Main]: ChromaPrint: 1.4.3
Debug [Main]: Vorbis: Xiph.Org libVorbis 1.3.6
Debug [Main]: libsndfile: libsndfile-1.0.28
Debug [Main]: FLAC: 1.3.3
Debug [Main]: libmp3lame: 3.100
The only option I see right now is to suppress all these logs.
The affected code is stateless. Printing the warning only once each session would require extensions including thread synchronization due to multi-threaded look up.