Re: Is it OK to perform logging while holding a LWLock?

On Tue, Mar 03, 2026 at 12:48:26PM -0800, Masahiko Sawada wrote:
> Also, if we reverse the ereport() and LWLockRelease() in the specific
> example in logicalctl.c, it would happen that a concurrent logical
> decoding activation writes the log "logical decoding is enabled upon
> creating a new logical replication slot" before the deactivation
> "logical decoding is disabled because there are no valid logical
> replication slots", confusing users since the logical decoding is
> active even though the last log saying "logical decoding is disabled".

I don't really understand why we need to care about changing these
code paths.  LWLocks are not bound to requirements like avoiding
elog() or Postgres-specific calls while being hold, so what we are
doing is basically fine.  None of the code paths changed here are
relevant performance-wise, as well.  Hence, why caring at all with
such changes?
--
Michael