On Wed, Sep 2, 2020 at 9:17 AM Tom Lane <t...@sss.pgh.pa.us> wrote: > > Amit Kapila <amit.kapil...@gmail.com> writes: > > Even if the relation is locked, background processes like checkpointer > > can still touch the relation which might cause problems. Consider a > > case where we extend the relation but didn't flush the newly added > > pages. Now during truncate operation, checkpointer can still flush > > those pages which can cause trouble for truncate. But, I think in the > > recovery path such cases won't cause a problem. > > I wouldn't count on that staying true ... > > https://www.postgresql.org/message-id/ca+hukgj8nrsqgkzensnrc2mfrobv-jcnacbyvtpptk2a9yy...@mail.gmail.com >
I don't think that proposal will matter after commit c5315f4f44 because we are caching the size/blocks for recovery while doing extend (smgrextend). In the above scenario, we would have cached the blocks which will be used at later point of time. -- With Regards, Amit Kapila.
