External project does not use parallel jobs

Code
4

There’s no way to access that information during a build. Ninja does not include a jobserver either, so make can’t share the job pool.

The best things available are:

  • If using the Makefiles generator and make internally, pass no -j flags and let the environment communicate the job server information.
  • If using Ninja (or any other non-Makefiles generator) is involved, pass explicit -j flags to the ExternalProject’s make command. I would recommend making a cache variable to allow for tuning this count.