The FileManager now automatically defers changes to the same file until a single write at "commit" time. This is useful for more complex metadata situations in which metadata may have intermediate state that is incomplete and an on-disk ITD representation would ordinarily be modified. The preservation of changes until commit time allows an extended period for the metadata to becomes finalised before on-disk ITD are changed. Of course these changes are also of more general benefit to non-ITD use cases, but it was these ITD-specific metadata considerations which motivated the enhancement.
Git commit 9328a4ad1528d3edef6f192788a725ea69f32788