Environment variables¶
Here are the environment variables CuPy uses.
CUDA_PATH |
Path to the directory containing CUDA.
The parent of the directory containing nvcc is
used as default.
When nvcc is not found, /usr/local/cuda is
used.
See Working with Custom CUDA Installation for details. |
CUPY_CACHE_DIR |
Path to the directory to store kernel cache.
${HOME}/.cupy/kernel_cache is used by default.
See Overview for details. |
CUPY_CACHE_SAVE_CUDA_SOURCE |
If set to 1, CUDA source file will be saved along with compiled binary in the cache directory for debug purpose. It is disabled by default. Note: source file will not be saved if the compiled binary is already stored in the cache. |
CUPY_DUMP_CUDA_SOURCE_ON_ERROR |
If set to 1, when CUDA kernel compilation fails, CuPy dumps CUDA kernel code to standard error. It is disabled by default. |
CUPY_CUDA_COMPILE_WITH_DEBUG |
If set to 1, CUDA kernel will be compiled with
debug information (--device-debug and
--generate-line-info ).
It is disabled by default. |
CUPY_GPU_MEMORY_LIMIT |
The amount of memory that can be allocated for
each device.
The value can be specified in absolute bytes or
fraction (e.g., "90%" ) of the total memory of
each GPU.
See Memory Management for details.
0 (unlimited) is used by default. |
CUPY_SEED |
Set the seed for random number generators. For
historical reasons CHAINER_SEED is used if
CUPY_SEED is unspecified. |
CUPY_EXPERIMENTAL_SLICE_COPY |
If set to 1, the following syntax is enabled:
cupy_ndarray[:] = numpy_ndarray . |
Moreover, as in any CUDA programs, all of the CUDA environment variables listed in the CUDA Toolkit Documentation will also be honored.
For installation¶
These environment variables are only used during installation.
CUDA_PATH |
See the description above. |
NVCC |
Define the compiler to use when compiling CUDA files. |
CUPY_PYTHON_350_FORCE |
Enforce CuPy to be installed against Python 3.5.0 (not recommended). |
CUPY_NVCC_GENERATE_CODE |
To build CuPy for a particular CUDA architecture. For example,
CUPY_NVCC_GENERATE_CODE=compute_60,sm_60 . When this is not
set, the default is to support all architectures. |