Environment Variables#

Note

The cuda-bindings runtime environment variables also affect cuda.core. See the cuda-bindings environment variables documentation.

Runtime Environment Variables#

  • CUDA_PYTHON_CUDA_PER_THREAD_DEFAULT_STREAM : When set to 1, the default stream is the per-thread default stream. When set to 0, the default stream is the legacy default stream. This defaults to 0, for the legacy default stream. See Stream Synchronization Behavior for an explanation of the legacy and per-thread default streams.

  • CUDA_PYTHON_DISABLE_MAJOR_VERSION_WARNING : When set to 1, suppresses warnings about CUDA major version mismatches between cuda-bindings and the installed driver. This warning occurs when cuda-bindings was built for a newer CUDA major version than the installed driver supports.

  • CUDA_CORE_DONT_FIX_TAB_COMPLETION : When set to 1, import cuda.core does not patch the standard library’s rlcompleter module. The patch works around a CPython bug (fixed in Python 3.13.13, 3.14.6 and 3.15) that makes tab completion fail on Cython properties, and it changes global interpreter state; set this variable to opt out. Unset, empty, and 0 leave the patch enabled; any other value disables it.