move description to separate file and cross reference

Author: ksimpson-work

cuda_bindings/docs/source/index.rst

@@ -9,6 +9,7 @@
    overview.md
    motivation.md
    release.md
+   environment_variables.md
    api.rst
 
 

cuda_bindings/docs/source/install.md

@@ -46,11 +46,9 @@ During the build process, environment variable `CUDA_HOME` or `CUDA_PATH` are us
 export CUDA_HOME=/usr/local/cuda
 ```
 
-Some other build time environment variables are as follows:
+See [Environment Variables](environment_variables.md) for a description of other builkd time environment variables.
 
-`CUDA_PYTHON_PARSER_CACHING` : bool, toggles the caching of parsed header files during the cuda-bindings build process. If caching is enabled (`CUDA_PYTHON_PARSER_CACHING` is True), the cache path is set to ./cache_<library_name>, where <library_name> is derived from the cuda toolkit libraries used to build cuda-bindings.
 
-`CUDA_PYTHON_PARALLEL_LEVEL` (previously `PARALLEL_LEVEL`) : int, sets the number of threads used in the compilation of cython files. This is passed as the `nthreads` argument to :meth:`cython.cythonize` and as the parallel attribute for building extension modules.
 
 ### In-place
 

cuda_bindings/setup.py

@@ -39,7 +39,9 @@
         DeprecationWarning,
         stacklevel=1,
     )
-nthreads = int(os.environ.get("CUDA_PYTHON_PARALLEL_LEVEL", "0") or "0")
+    nthreads = int(os.environ.get("PARALLEL_LEVEL", "0"))
+else:
+    nthreads = int(os.environ.get("CUDA_PYTHON_PARALLEL_LEVEL", "0") or "0")
 PARSER_CACHING = os.environ.get("CUDA_PYTHON_PARSER_CACHING", False)
 PARSER_CACHING = bool(PARSER_CACHING)