Give preference to path with more XGMI connections

[ROCm/rccl commit: b3c9852634]

projects/rccl/tools/topo_expl/topo_expl.cpp

@@ -76,6 +76,7 @@ const char *model_descriptions[] = {
   "4 nodes with 8 VEGA20 GPUs XGMI 4P2H 1 NIC",
   "4 nodes with 8 VEGA20 GPUs XGMI 4P2H 1 NIC 2nd Hive",
   "4 nodes with 8 VEGA20 GPUs XGMI 4P2H 2 NIC",
+  "single node 8 VEGA20 Rome",
   NULL,
 };
 
@@ -166,6 +167,10 @@ int main(int argc,char* argv[])
         network.AddNode(node);
       }
       break;
+    case 13:
+      node = new NodeModel("topo_8p_rome.xml");
+      network.AddNode(node);
+      break;
     default:
       printf("Invalid model_id %d\n", model_id);
       exit(0);