To make the UCX module a bit smarter, and try to keep CUDA settings if they were selected before

Custom_Hooks/eb_hooks.py

@@ -404,8 +404,15 @@ def inject_ucx_tweaks(ec):
     if ec.name in 'UCX' and install_path().lower().startswith('/p/software'):
         key = "modluafooter"
         value = '''
-if not ( isloaded("UCX-settings") ) then
-    load("UCX-settings")
+-- This weird construct is to prevent lmod from loading the default settings when reloading/swapping UCX
+-- Unfortunately we can't do better (like preserving the UCX transport for CUDA, since the loaded
+-- UCX-settings module is lost during the reload
+if mode()=="load" then
+    if isloaded("mpi-settings/CUDA") then
+        try_load("UCX-settings/RC-CUDA")
+    else
+        try_load("UCX-settings")
+    end
 end
         '''
         if key in ec_dict: