Hi,
I'm having the same Issue.
I would like to limit the CPU usage from youtube-dl. I've seen there is a command line switch --postprocessor-args '-threads N'.
Maybe with help of this switch it would be possible to limit the usage to one core only?
Another strange thing is that for every song a new youtube-dl Process is spawned, but the old ones are staying alive.
After an hour i've 30 youtube-dl Processes running and VPS Server is getting really slow.