.. index::
    double: CUDA; options

CUDA specific options
---------------------

This is the list of CUDA specific options:

.. tabularcolumns:: |l|l|J|

+----------------------------+-------------------------+----------------------------------------------------+
|  NX_ARGS option            |  Environment variable   | Description                                        |
+============================+=========================+====================================================+
| --disable-cuda             |  NX_DISABLECUDA         | Enable or disable the use of GPUs with CUDA        |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpus                     |  NX_GPUS                | Defines the maximum number of GPUs to use          |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-warmup               |  NX_GPUWARMUP           | Enable or disable warming up the GPU before        |
|                            |                         | running user's code                                |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-prefetch             |  NX_GPUPREFETCH         | Set whether data prefetching must be activated     |
|                            |                         | or not                                             |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-overlap              |  NX_GPUOVERLAP          | Set whether GPU computation should be              |
|                            |                         | overlapped with all data transfers, whenever       |
|                            |                         | possible, or not                                   |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-overlap-inputs       |  NX_GPUOVERLAP_INPUTS   | Set whether GPU computation should be              |
|                            |                         | overlapped with host --> device data transfers,    |
|                            |                         | whenever possible, or not                          |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-overlap-outputs      |  NX_GPUOVERLAP_OUTPUTS  | Set whether GPU computation should be overlapped   |
|                            |                         | with device --> host data transfers, whenever      |
|                            |                         | possible, or not                                   |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-max-memory           |  NX_GPUMAXMEM           | Defines the maximum amount of GPU memory           |
|                            |                         | (in bytes) to use for each GPU. If this number     |
|                            |                         | is below 100, the amount of memory is taken as a   |
|                            |                         | percentage of the total device memory              |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-cache-policy         |  NX_GPU_CACHE_POLICY    | Defines the cache policy for GPU architectures:    |
|                            |                         | write-through / write-back / do not use cache      |
+----------------------------+-------------------------+----------------------------------------------------+
| --gpu-cublas-init          |  NX_GPUCUBLASINIT       | Enable or disable CUBLAS initialization            |
+----------------------------+-------------------------+----------------------------------------------------+

Following table summarizes valid and default values:

.. tabularcolumns:: |l|l|l|l|

+----------------------------+-------------------------+--------------------+--------------+
|  NX_ARGS option            |  Environment variable   |  Values            |  Default     |
+============================+=========================+====================+==============+
| --disable-cuda             |  NX_DISABLECUDA         |  yes / no          |  Enabled     |
+----------------------------+-------------------------+--------------------+--------------+
| --gpus                     |  NX_GPUS                |  integer           |  All GPUs    |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-warmup               |  NX_GPUWARMUP           |  yes / no          |  Enabled     |
|                            |                         |                    |              |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-prefetch             |  NX_GPUPREFETCH         |  yes / no          |  Disabled    |
|                            |                         |                    |              |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-overlap              |  NX_GPUOVERLAP          |  yes / no          |  Disabled    |
|                            |                         |                    |              |
|                            |                         |                    |              |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-overlap-inputs       |  NX_GPUOVERLAP_INPUTS   |  yes / no          |  Disabled    |
|                            |                         |                    |              |
|                            |                         |                    |              |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-overlap-outputs      |  NX_GPUOVERLAP_OUTPUTS  |  yes / no          |  Disabled    |
|                            |                         |                    |              |
|                            |                         |                    |              |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-max-memory           |  NX_GPUMAXMEM           |  positive integer  |  No limit    |
|                            |                         |                    |              |
|                            |                         |                    |              |
|                            |                         |                    |              |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-cache-policy         |  NX_GPU_CACHE_POLICY    |  wt/wb/nocache     |  wb          |
|                            |                         |                    |              |
+----------------------------+-------------------------+--------------------+--------------+
| --gpu-cublas-init          |  NX_GPUCUBLASINIT       |  yes / no          |  Disabled    |
+----------------------------+-------------------------+--------------------+--------------+