diff options
| author | Ludovic Courtès <ludovic.courtes@inria.fr> | 2019-11-15 17:15:05 +0100 |
|---|---|---|
| committer | Ludovic Courtès <ludo@gnu.org> | 2019-11-15 17:52:45 +0100 |
| commit | faab7082ab9587b71ca5ae8becdf72234f3c51d7 (patch) | |
| tree | 6a27e070f9d289e6ebd44d42014b4e7a7eacc46b /gnu/packages/patches | |
| parent | 348caf3d2c0e5a1d842c16cf6246f6d84004ad3f (diff) | |
gnu: openmpi: Raise the priority of the PSM2 component.
This allows us to get better performance by default on machines with
OmniPath hardware.
* gnu/packages/patches/openmpi-psm2-priority.patch: New file.
* gnu/packages/mpi.scm (openmpi)[source]: Use it.
* gnu/local.mk (dist_patch_DATA): Add it.
Diffstat (limited to 'gnu/packages/patches')
| -rw-r--r-- | gnu/packages/patches/openmpi-psm2-priority.patch | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/gnu/packages/patches/openmpi-psm2-priority.patch b/gnu/packages/patches/openmpi-psm2-priority.patch new file mode 100644 index 0000000000..d9dd558010 --- /dev/null +++ b/gnu/packages/patches/openmpi-psm2-priority.patch @@ -0,0 +1,21 @@ +PSM2 is the only valid implementation for OmniPath (OPA). UCX also +supports OmniPath, but it does so via Verbs, thus getting much lower +performance (typically 3 GiB/s instead of 10 GiB/s). + +To work around that, give the mtl_psm2 component a higher priority +than the pml_ucx component. + +See <https://www.mail-archive.com/users@lists.open-mpi.org/msg33581.html>. + +--- openmpi-4.0.2/ompi/mca/mtl/psm2/mtl_psm2_component.c 2019-11-15 17:06:15.142076840 +0100 ++++ openmpi-4.0.2/ompi/mca/mtl/psm2/mtl_psm2_component.c 2019-11-15 17:06:22.242009379 +0100 +@@ -126,7 +126,7 @@ ompi_mtl_psm2_component_register(void) + setenv("PSM2_DEVICES", "self,shm", 0); + } + +- param_priority = 40; ++ param_priority = 55; + (void) mca_base_component_var_register (&mca_mtl_psm2_component.super.mtl_version, + "priority", "Priority of the PSM2 MTL component", + MCA_BASE_VAR_TYPE_INT, NULL, 0, 0, + |