bpo-36786: Run compileall in parallel during "make install" (GH-13078)
diff --git a/Doc/library/compileall.rst b/Doc/library/compileall.rst
index 5e08616..bb5000a 100644
--- a/Doc/library/compileall.rst
+++ b/Doc/library/compileall.rst
@@ -158,7 +158,8 @@
The argument *workers* specifies how many workers are used to
compile files in parallel. The default is to not use multiple workers.
If the platform can't use multiple workers and *workers* argument is given,
- then sequential compilation will be used as a fallback. If *workers* is
+ then sequential compilation will be used as a fallback. If *workers*
+ is 0, the number of cores in the system is used. If *workers* is
lower than ``0``, a :exc:`ValueError` will be raised.
*invalidation_mode* should be a member of the
@@ -184,6 +185,9 @@
.. versionchanged:: 3.7
The *invalidation_mode* parameter was added.
+ .. versionchanged:: 3.8
+ Setting *workers* to 0 now chooses the optimal number of cores.
+
.. function:: compile_file(fullname, ddir=None, force=False, rx=None, quiet=0, legacy=False, optimize=-1, invalidation_mode=py_compile.PycInvalidationMode.TIMESTAMP)
Compile the file with path *fullname*. Return a true value if the file