What is the optimal value of the -j flag for make ? I know that all my source is free of errors.

Is it the number of cores? Or the number of logical processors?

  • IIRC make will use whatever is available without using the -j option. I've always used it to limit the resources being used so that my machine is still usable for other tasks while something big builds. – ivanivan Jun 12 '17 at 4:58
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    @ivanivan it won’t build in parallel by default, you need to use -j if you want parallel builds. – Stephen Kitt Jun 12 '17 at 5:38