diff --git a/opal/mca/btl/openib/btl_openib_component.c b/opal/mca/btl/openib/btl_openib_component.c index 85ba474241..301df26097 100644 --- a/opal/mca/btl/openib/btl_openib_component.c +++ b/opal/mca/btl/openib/btl_openib_component.c @@ -2577,6 +2577,15 @@ btl_openib_component_init(int *num_btl_modules, opal_leave_pinned_pipeline = 0; } +#if OPAL_CUDA_SUPPORT + if (mca_btl_openib_component.cuda_want_gdr && (0 == opal_leave_pinned)) { + opal_show_help("help-mpi-btl-openib.txt", + "CUDA_gdr_and_nopinned", true, + opal_process_info.nodename); + goto no_btls; + } +#endif /* OPAL_CUDA_SUPPORT */ + index = mca_base_var_find("ompi", "btl", "openib", "max_inline_data"); if (index >= 0) { if (OPAL_SUCCESS == mca_base_var_get_value(index, NULL, &source, NULL)) { diff --git a/opal/mca/btl/openib/help-mpi-btl-openib.txt b/opal/mca/btl/openib/help-mpi-btl-openib.txt index 031d10142b..94dcc7b8f5 100644 --- a/opal/mca/btl/openib/help-mpi-btl-openib.txt +++ b/opal/mca/btl/openib/help-mpi-btl-openib.txt @@ -692,3 +692,11 @@ You cannot have fork support and CUDA GPU Direct RDMA support on at the same time. Please disable one of them. Deactivating the openib BTL. Local host: %s +# +[CUDA_gdr_and_nopinned] +You requested to run with CUDA GPU Direct RDMA support but also with +"leave pinned" turned off. This will result in very poor performance +with CUDA GPU Direct RDMA. Either disable GPU Direct RDMA support or +enable "leave pinned" support. Deactivating the openib BTL. + + Local host: %s