Subject: Re: Null value returned by function pg_last_wal_receive_lsn()
 inLogical Replication
To: pgsql-admin@lists.postgresql.org
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From: Mark Kirkwood <mark.kirkwood@catalyst.net.nz>
Message-ID: <053b174e-b186-86f9-b0cb-1d80e6fb236e@catalyst.net.nz>
Date: Mon, 15 Oct 2018 15:22:34 +1300
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I think those functions really only make sense for physical replication.

Looking at the docs e.g: 
https://www.postgresql.org/docs/10/static/logical-replication-monitoring.html 
they appear to *suggest* that monitoring should be similar...some 
clarification there is probably in order!

However they also say to use the pg_stat_subsubscription view to monitor 
your logical rep, e.g: here's what my pgbench dataset subscription looks 
like:

bench=# SELECT * FROM pg_stat_subscription;
  subid | subname | pid  | relid | received_lsn | 
last_msg_send_time       |     last_msg_receipt_time     | 
latest_end_lsn |        latest_end_time
-------+---------+------+-------+--------------+-------------------------------+-------------------------------+----------------+-------------------------------
  16409 | pgbench | 8840 |       | 0/51EB3A20   | 2018-10-15 
15:16:38.501061+13 | 2018-10-15 15:16:38.501103+13 | 0/51EB3A20     | 
2018-10-15 15:16:38.501061+13
(1 row)

Cheers

Mark


On 11/10/18 02:43, pavan95 wrote:
> Hi Soumitra,
>
> Could you please explain the reason behind taking the
> pg_current_xlog_insert_location() & restart_lsn?
>
>
> Regards,
> Pavan
>
>
>
> --
> Sent from: http://www.postgresql-archive.org/PostgreSQL-admin-f2076596.html
>