Re: Replication lag from transaction logs - Mailing list pgsql-admin

From Debraj Manna
Subject Re: Replication lag from transaction logs
Date
Msg-id CAF6DVKPchrtTnTfrh3fygfZb2BSSW_nQgK_z0x+sjT4t=stMxQ@mail.gmail.com
Whole thread Raw
In response to Re: Replication lag from transaction logs  (Keith <keith@keithf4.com>)
Responses Re: Replication lag from transaction logs  (Keith <keith@keithf4.com>)
List pgsql-admin
Thanks Keith I am looking something like the solution you suggested.

Once I run pg_controldata on the slave data directory it will be give me the latest checkpoint like below. Can you let me know a bit more detail on how can I get the approximate lag in the slave in bytes from this?

Latest checkpoint location: 2F9/B38DE758




On Mon 18 Jun, 2018, 6:53 PM Keith, <keith@keithf4.com> wrote:
You can use pg_controldata on any data directory to get its rough position in WAL replay, even when the database isn't running


On Mon, Jun 18, 2018 at 8:56 AM, Fabio Pardi <f.pardi@portavita.eu> wrote:

That I know, if standby is down, you cannot know exactly the last applied transaction log file.

But you could get a gross estimate if you check how many WAL files is the standby behind, just listing the WAL files on the master and on the standby.

Given that you can login on the standby machine.

regards,

fabio pardi


On 18/06/18 14:43, Debraj Manna wrote:
Is it possible to figure out the replication lag from transaction log files in the slave and master without querying postgres on the slave? Basically figuring out the replication lag in a slave when the postgres is down in that slave.


pgsql-admin by date:

Previous
From: Keith
Date:
Subject: Re: Replication lag from transaction logs
Next
From: Keith
Date:
Subject: Re: Replication lag from transaction logs