diff --git a/src/Storage.cpp b/src/Storage.cpp
index 781cda05f4..df1f612be3 100644
--- a/src/Storage.cpp
+++ b/src/Storage.cpp
@@ -803,6 +803,7 @@ const char* Storage::SavePersistent(StringRef filename, bool periodic) const {
     err = "error saving file";
     goto done;
   }
+  os.close();
 
   // Safely move to real file.  We ignore any failures related to the backup.
   std::remove(bak.c_str());