Opam jobs parallelism?

[Chet_Murthy]

Lately I install a large number of opam packages regularly (blow away a switch, recreate, reinstall packages) and I’m using machines with 16 cores. When I use “make”, I can specify “-j32” and pretty much use up the entire machine, but when I’m installing with opam, it seems that even specifying “-j32” for “opam install” doesn’t actually induce any significant parallelism.

Does anybody know if there’s a way to push down the “-j32” to the make that opam will invoke ?

[kit-ty-kate]

The %{jobs}% global variable is always available and returns by default the number of available cores of the machine - 1.

For example, when building the OCaml compiler the variable is used this way:

ocaml/opam-repository/blob/e0298ebc989d5357a09b85f353f52ad12ce73ba2/packages/ocaml-base-compiler/ocaml-base-compiler.5.2.1/opam#L74