On Wed, Oct 19, 2016 at 08:33:20AM -0400, Robert Haas wrote: > On Tue, Oct 18, 2016 at 4:33 PM, Josh Berkus <j...@agliodbs.com> wrote: > > Based on that argument, we would never be able to remove any > > configuration parameter ever. > > Well... no. Based on that argument, we should only remove > configuration parameters if we're fairly certain that they are not > useful any more, which will be rare, but is not never. I agree that > *if* vacuum_defer_cleanup_age is no longer useful, it should be > removed. I'm just not convinced that it's truly obsolete, and you > haven't really offered much of an argument for that proposition. It > does something sufficiently different from hot_standby_feedback that > I'm not sure it's accurate to say that one can substitute for the > other, and indeed, I see Andres has already suggested some scenarios > where it could still be useful. > > Actually, I think vacuum_defer_cleanup_age is, and always has been, an > ugly hack. But for some people it may be the ugly hack that is > letting them continue to use PostgreSQL.
I see vacuum_defer_cleanup_age as old_snapshot_threshold for standby servers --- it cancels transactions rather than delaying cleanup. -- Bruce Momjian <br...@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + As you are, so once was I. As I am, so you will be. + + Ancient Roman grave inscription + -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers