metadata reshaping takes too much memory and overload when retrieve = F

When retrieve = F, Start() should only detect the data location, identify the data size, and return metadata if required. But when reshaping is used and metadata needs to be reshaped as well, Start() seems to have a memory problem during the reshaping process. Therefore, retrieve = F may still kill the terminal if the detected data size is big. For now, the problematic part seems to be in the inner function rebuild_array_merge_split().