guix/gnu/packages/patches/openmpi-mtl-priorities.patch
Ludovic Courtès 68ac34e120
gnu: openmpi: Increase priority of the PSM component.
* gnu/packages/patches/openmpi-psm2-priority.patch: Rename to...
* gnu/packages/patches/openmpi-mtl-priorities.patch: ... this.  Add hunk
to change the priority of PSM.
* gnu/packages/mpi.scm (openmpi)[source]: Adjust accordingly.
* gnu/local.mk (dist_patch_DATA): Likewise.
2019-11-29 15:54:19 +01:00

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1.6 KiB
Diff

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,
Likewise for PSM: we want InfiniPath to be taken care of by PSM, not by UCX,
since UCX achieves worse performance.
--- openmpi-4.0.2/ompi/mca/mtl/psm/mtl_psm_component.c
+++ openmpi-4.0.2/ompi/mca/mtl/psm/mtl_psm_component.c
@@ -92,7 +92,7 @@ ompi_mtl_psm_component_register(void)
/* set priority high enough to beat ob1's default */
- param_priority = 30;
+ param_priority = 54;
(void) mca_base_component_var_register (&mca_mtl_psm_component.super.mtl_version,
"priority", "Priority of the PSM MTL component",
MCA_BASE_VAR_TYPE_INT, NULL, 0, 0,