RE: How do I only use one processor core/thread when building?

Amanda Hsieh — Mon, 16 Mar 2026 14:45:48 GMT

Hi Will,

[quote user=""]I'd like to configure the development environment (nRF Connect extension in VS Code) to only use a single processor core on the PC when building. [/quote]

The build system uses ninja under the hood, which by default uses all available CPU cores. You can control this with the -j option via west build. See Build parallelism

[quote user=""]I tried the AI suggestion of adding "-o=-j1" as an extra CMake argument in the build configuration but it appears to not do anything (hallucination? ignored?)[/quote]

You can try to use nRF Connect terminal to build with the command.

[quote user=""]is there any way to automatically have the build "log" stream to a file so I don't have to manually cut and paste from the terminal window every time? [/quote]

Check out this post: In nrf connect for vscode, how to store the project build log in a file

Regards,
Amanda H.