On Wed, Sep 29, 2021 at 8:18 AM Antonin Houska <a...@cybertec.at> wrote: > I'm just trying to use the existing infrastructure: the effect of DROP TABLE > also appear to be performed by the checkpointer. However I don't know why the > unlinks need to be performed by the checkpointer.
For DROP TABLE, we leave an empty file (I've been calling it a "tombstone file") so that GetNewRelFileNode() won't let you reuse the same relfilenode in the same checkpoint cycle. One reason is that wal_level=minimal has a data-eating crash recovery failure mode if you reuse a relfilenode in a checkpoint cycle.
