Fix typo

doc/usage/configuration.rst

@@ -795,7 +795,7 @@ General configuration
    the parallel write phase. When active, the event :event:`doctree-resolved` as
    well as the builder function ``write_doc_serialized`` also run in parallel.
    Parallel post-transformation can greatly improve build time for extensions that
-   do heave computation in that phase. Depending on machine core count and project
+   do heavy computation in that phase. Depending on machine core count and project
    size, a build time reduction by a factor of 2 to 4 and even more was observed.
    The feature flag does nothing in case parallel writing is not used.
 

sphinx/testing/fixtures.py

@@ -145,6 +145,7 @@ def app(
     """
     args, kwargs = app_params
     app_ = make_app(*args, **kwargs)
+    app_.env.config.enable_parallel_post_transform = True
     yield app_
 
     print('# testroot:', kwargs.get('testroot', 'root'))
@@ -189,6 +190,7 @@ def make(*args: Any, **kwargs: Any) -> SphinxTestApp:
         kwargs.setdefault('status', status)
         kwargs.setdefault('warning', warning)
         app_: Any = SphinxTestApp(*args, **kwargs)
+        # app_.env.config.enable_parallel_post_transform = True
         apps.append(app_)
         if test_params['shared_result']:
             app_ = SphinxTestAppWrapperForSkipBuilding(app_)

sphinx/testing/util.py

@@ -91,8 +91,8 @@ def __init__(
         status: IO | None = None,
         warning: IO | None = None,
         tags: list[str] | None = None,
-        docutils_conf: str | None = None,
-        parallel: int = 0,
+        docutilsconf: str | None = None,
+        parallel: int = 4,
     ) -> None:
         assert srcdir is not None
 

sphinx/util/parallel.py

@@ -149,7 +149,7 @@ def make_chunks(arguments: Sequence[str], nproc: int, maxbatch: int = 10) -> lis
     chunksize = nargs // nproc
     if chunksize >= maxbatch:
         # try to improve batch size vs. number of batches
-        chunksize = int(sqrt(nargs / nproc * maxbatch))
+        chunksize = int(sqrt(sqrt(nargs / nproc * maxbatch)))
     if chunksize == 0:
         chunksize = 1
     nchunks, rest = divmod(nargs, chunksize)

tox.ini

@@ -24,7 +24,7 @@ setenv =
     PYTHONWARNINGS = error
     PYTEST_ADDOPTS = {env:PYTEST_ADDOPTS:} --color yes
 commands=
-    python -X dev -X warn_default_encoding -m pytest --durations 25 {posargs}
+    python -X dev -X warn_default_encoding -m pytest -n 4 --durations 25 {posargs}
 
 [testenv:docs]
 basepython = python3