Visible to Intel only — GUID: GUID-F61CAB80-1787-4D1E-8C1F-56F34631F3A2
Visible to Intel only — GUID: GUID-F61CAB80-1787-4D1E-8C1F-56F34631F3A2
GPU Support
This section provides information about the following GPU devices support in Intel® MPI Library:
These features require the Level-Zero* library or CUDA* Library to be installed on the nodes. All environment variables have I_MPI_OFFLOAD_* prefix.
Current support is limited to Intel GPUs and Nvidia* GPUs only.
I_MPI_OFFLOAD
Set this environment variable to enable all GPU features.
Syntax
I_MPI_OFFLOAD=<value>
Arguments
Value | Description |
---|---|
0 | Disabled. This is the default value. |
1 | Enabled. |
Description
Set this environment variable to enable all GPU features such as GPU pinning and GPU buffers support, which give you ability to distribute devices between MPI ranks and provide a pointer of an offloaded memory to MPI functions.
I_MPI_OFFLOAD_MODE
Select the API for GPU/accelerator offloading.
Syntax
I_MPI_OFFLOAD_PRINT_TOPOLOGY=<value>
Arguments
Value | Description |
---|---|
auto | Automatically identify GPU backend. This is the default value. |
level_zero | Use Level-Zero API and library for GPU operations. |
cuda | Use CUDA Driver API and library for GPU operations. |
Description
Set this environment variable to select the API for GPU/accelerator offloading.
I_MPI_OFFLOAD_SYMMETRIC
Enable/disable an assumption that all buffers in an operation have the same type.
Syntax
I_MPI_OFFLOAD_SYMMETRIC=<value>
Arguments
Value | Description |
---|---|
0 | Disabled. This is the default value. |
1 | Enabled. |
Description
Set this environment variable to enable/disable an assumption that all buffers in an operation have the same type. That is, buffers are allocated on GPU or HOST only.
Setting this variable optimizes device->device communications but disables handling of host->device and device->host cases.
I_MPI_OFFLOAD_LEVEL_ZERO_LIBRARY
Specify the name and full path to the Level-Zero library.
Syntax
I_MPI_OFFLOAD_LEVEL_ZERO_LIBRARY="<path>/<name>"
Arguments
Argument | Description |
---|---|
<path> | Full path to the Level-Zero library. |
<name> | Name of the Level-Zero library. |
Description
Set this environment variable to specify the name and full path to Level-Zero library. Set this variable if Level-Zero is not located in the default path. Default value: libze_loader.so.
I_MPI_OFFLOAD_CUDA_LIBRARY
Specify the name and full path to the CUDA Driver library.
Arguments
Value | Description |
---|---|
<path> | Full path to the CUDA Driver library. |
<name> | Name of the CUDA Driver library. |
Description
Set this environment variable to specify the name and full path to CUDA Driver library. Set this variable if CUDA is not located in the default path. Default value: ** libcuda.so.