On 2021-Nov-10, Andres Freund wrote:
> > Reverts 27838981be9d (some comments are kept). Per discussion, it does
> > not seem safe to relax the lock level used for this; in order for it to
> > be safe, there would have to be memory barriers between the point we set
> > the flag and the point we set the trasaction Xid, which perhaps would
> > not be so bad; but there would also have to be barriers at the readers'
> > side, which from a performance perspective might be bad.
> >
> > Now maybe this analysis is wrong and it *is* safe for some reason, but
> > proof of that is not trivial.
>
> I just noticed that this commit (dcfff74fb16) didn't revert the change of lock
> level in ReplicationSlotRelease(). Was that intentional?
Hmm, no, that seems to have been a mistake. I'll restore it.
--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/
"El miedo atento y previsor es la madre de la seguridad" (E. Burke)