How to Limit CPU Usage

[Haravikk]

Okay, so I mostly use VLC for transcoding files, and it will normally use all cores of my machine. Now this is fine most of the time, but it interferes with running some programs while VLC transcodes in the background.

Since I don't normally need VLC to work as fast as possible, I'm happy for it to just run in the background with whatever free CPU load is left, but I'm not sure how best to restrict it. Is there an easy way to limit VLC to a smaller number of cores, or to lower its priority so other tasks will get the CPU time that they need?

Ideally without running VLC from command line, as I prefer to just open it as a regular app.

[Jean-Baptiste Kempf]

Yes, you can limit encoding threads, in x264 preferences.

[luxigo]

For linux theres a package name "cpulimit", that allowed me cool my CPU down to 70°C (instead of 95°C) while loading a huge m3u playlist with remote files... (!)

[fkuehne]

There are similar tools for the Mac.

Alternatively, as JB suggested, you can dive deep inside VLC's advanced preferences (VLC -> Preferences -> Show All) to the transcoding settings to limit the number of threads. You find the option "Number of Threads" in "Stream output" -> "Sout stream" -> "transcode" at the very bottom. "0" is the default value which means an "optimal" number of threads aka logical number of CPU cores * 1.5. Entering any integer will limit the number of used cores to that value.

Note that setting this option requires a restart of VLC.