Merge pull request #6082 from matcabral/lower_mtl_ofi_p

MTL/OFI: Lower priority when all procs are local

Author: matcabral

ompi/mca/mtl/ofi/mtl_ofi_component.c

@@ -116,8 +116,21 @@ ompi_mtl_ofi_component_register(void)
     int ret;
     mca_base_var_enum_t *new_enum = NULL;
     char *desc;
+    int num_total_procs = (int)ompi_process_info.num_procs;
+    /* num_local_peers does not include us in
+     * its calculation, so adjust for that */
+    int num_local_procs = (int)(1 + ompi_process_info.num_local_peers);
+
+    /* Lower priority when all porcesses are loal (vader is faster for shm).
+     * However, if running only one process assume it is ompi_info or this
+     * is most likely going to spawn.
+     */
+    if ((num_local_procs == num_total_procs) && (1 < num_total_procs)) {
+        param_priority = 10;
+    } else {
+        param_priority = 25;   /* for now give a lower priority than the psm mtl */
+    }
 
-    param_priority = 25;   /* for now give a lower priority than the psm mtl */
     mca_base_component_var_register(&mca_mtl_ofi_component.super.mtl_version,
                                     "priority", "Priority of the OFI MTL component",
                                     MCA_BASE_VAR_TYPE_INT, NULL, 0, 0,