diff --git a/mysql-test/mysql-test-run.pl b/mysql-test/mysql-test-run.pl
index f43cadd3784..203f964c72e 100755
--- a/mysql-test/mysql-test-run.pl
+++ b/mysql-test/mysql-test-run.pl
@@ -873,6 +873,10 @@ sub command_line_setup () {
 	last;
       }
     }
+
+    # point vardir to the mem location
+    $opt_vardir= $opt_mem;
+    undef $opt_mem;
   }
 
   # --------------------------------------------------------------------------