On Thu, May 7, 2020 at 11:04 PM David Rowley <dgrowle...@gmail.com> wrote:
> On Fri, 8 May 2020 at 13:51, github kran <githubk...@gmail.com> wrote: > > I can't either DROP or ALTER any other tables ( REMOVE Inheritance > for any of old tables where the WRITES are not getting written to). Any of > the ALTER TABLE OR DROP TABLE DDL's arer not getting exeucted even I > WAITED FOR SEVERAL MINUTES , so I have terminated those queries as I didn't > have luck. > > The auto-vacuum freeze holds an SharedUpdateExclusiveLock on the table > being vacuumed. If you try any DDL that requires an > AccessExclusiveLock, it'll have to wait until the vacuum has > completed. If you leave the DDL running then all accesses to the table > will be queued behind the ungranted AccessExclusiveLock. It's likely > a good idea to always run DDL with a fairly short lock_timeout, just > in case this happens. > * How much value I can assign to lock_timeout so that I dont get into trouble to test my DDL commands and without impacting other sessions.* > > > 3) Can I increase the autovacuum_freeze_max_age on the tables on > production system ? > > > Yes, but you cannot increase the per-table setting above the global > setting. Changing the global setting requires a restart. > > How can I change the value of the global setting of the autovacuum_freeze_max_Age value. > David >
