> On Fri, Nov 22, 2019 at 01:20:59PM +0000, Zwettler Markus (OIZ) wrote: > > I came up with the following query which should return any apply lag in seconds. > > > > select coalesce(replay_delay, 0) replication_delay_in_sec from ( > > select datname, > > ( > > select case > > when received_lsn = latest_end_lsn then 0 > > else extract(epoch > > from now() - latest_end_time) > > end > > from pg_stat_wal_receiver > > ) replay_delay > > from pg_database > > where datname = current_database() > > ) xview; > > > > > > I would expect delays >0 in case SYNC or ASYNC replication is somehow > > behind. We will do a warning at 120 secs and critical at 300 secs. > > pg_stat_wal_receiver is available only on the receiver, aka the standby so it would > not really be helpful on a primary. On top of that streaming replication is system- > wide, so there is no actual point to look at databases either. > > > Would this do the job or am I missing something here? > > Here is a suggestion for Nagios: hot_standby_delay, as told in > https://github.com/bucardo/check_postgres/blob/master/check_postgres.pl > -- > Michael I don't want to use check_hot_standby_delay as I would have to configure every streaming replication configuration separately with nagios. I want a generic routine which I can load on any postgres server regardless of streaming replication or database role. The query would return >0 if streaming replication falls behind and 0 in all other cases (replication or not). Checking streaming replication per database doesn't make any sense to me. Markus
