Re: logical replication and statistics

On 25/09/17 13:33, Pavel Stehule wrote:
>
>
> 2017-09-25 13:12 GMT+02:00 Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com
> <mailto:sawada(dot)mshk(at)gmail(dot)com>>:
>
> On Mon, Sep 25, 2017 at 12:58 AM, Pavel Stehule
> <pavel(dot)stehule(at)gmail(dot)com <mailto:pavel(dot)stehule(at)gmail(dot)com>> wrote:
> > Hi
> >
> > I did trivial example of logical replication (one table, one publication,
> > one subscription)
> >
> > I am little bit surprised so after some work - the replication is working,
> > the statistics are empty
> >
> > #master
> > postgres=# select * from pg_stat_replication ;
> > (0 rows)
> >
> > #slave
> > postgres=# select * from pg_stat_subscription ;
> > -[ RECORD 1 ]---------+---------
> > subid                 | 16472
> > subname               | test_sub
> > pid                   |
> > relid                 |
> > received_lsn          |
> > last_msg_send_time    |
> > last_msg_receipt_time |
> > latest_end_lsn        |
> > latest_end_time       |
> >
> > Should be some enabled?
> >
>
> If the subscription is disabled, the statistics of subscription is
> empty and no wal sender processes launch. The test_sub can start the
> replication by ALTER SUBSCRIPTION test_sub ENABLE.
>
>
> I used this subscriptions for and it was warking.

If there is no pid, the worker is not running. And if there is nothing
in pg_stat_replication on master, the walsender is not running either,
so it seems like it's not actually working.

--
Petr Jelinek http://www.2ndQuadrant.com/
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