diff --git a/svnmigrate.sh b/svnmigrate.sh
index 53786cf..5349d65 100644
--- a/svnmigrate.sh
+++ b/svnmigrate.sh
@@ -14,8 +14,8 @@ function migrate() {
 }
 
 function clean() {
-    # clean up git tree thoroughly
-    /usr/bin/git gc --aggressive
+    # clean up git tree
+    /usr/bin/git gc --auto
 }
 
 function push() {