MIME-Version: 1.0
References: 
 <OSBPR01MB48887CA8F40C8D984A6DC00CED199@OSBPR01MB4888.jpnprd01.prod.outlook.com>
 <CAD21AoAixHnpjG-TtnSejJ2Dv1VsrzGr3oVPSRFhYjz3Z8_XZA@mail.gmail.com>
 <OSBPR01MB4888D9048D3D7E7C3D035D54EDEF9@OSBPR01MB4888.jpnprd01.prod.outlook.com>
 <CAD21AoCbj6YBNmdG9gAXf=dPE+bdY95ENwkh4q5wPL0q=qMzVw@mail.gmail.com>
 <CAA4eK1+tOV-+ssGjj1zq+nAL8a9LfPsxbtyupZGvZ0U7nV0A7g@mail.gmail.com>
 <CAD21AoAO0004L1kv9+uArrhT7d=vFj=2ZUKFbUfpZnHJku-37g@mail.gmail.com>
In-Reply-To: 
 <CAD21AoAO0004L1kv9+uArrhT7d=vFj=2ZUKFbUfpZnHJku-37g@mail.gmail.com>
From: Amit Kapila <amit.kapila16@gmail.com>
Date: Tue, 3 Aug 2021 14:41:12 +0530
Message-ID: 
 <CAA4eK1+CfMrJeA8TR__uFMQVZk50L+OGUEW-8h5G0hD_erfaSw@mail.gmail.com>
Subject: Re: Failed transaction statistics to measure the logical replication
 progress
To: Masahiko Sawada <sawada.mshk@gmail.com>
Cc: "osumi.takamichi@fujitsu.com" <osumi.takamichi@fujitsu.com>,
	"pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Content-Type: text/plain; charset="UTF-8"
Archived-At: 
 <https://www.postgresql.org/message-id/CAA4eK1%2BCfMrJeA8TR__uFMQVZk50L%2BOGUEW-8h5G0hD_erfaSw%40mail.gmail.com>
Precedence: bulk

On Tue, Aug 3, 2021 at 10:59 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> On Tue, Aug 3, 2021 at 11:47 AM Amit Kapila <amit.kapila16@gmail.com> wrote:
> >
> > On Mon, Aug 2, 2021 at 1:13 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> > >
> > > On Mon, Aug 2, 2021 at 2:52 PM osumi.takamichi@fujitsu.com
> > > <osumi.takamichi@fujitsu.com> wrote:
> > > >
> > > >
> > > > Accordingly, I'm thinking to have unsuccessful and successful stats on the sub side.
> > > > Sawada-san is now implementing a new view in [1].
> > > > Do you think that I should write a patch to introduce a new separate view
> > > > or write a patch to add more columns to the new view "pg_stat_subscription_errors" that is added at [1] ?
> > >
> > > pg_stat_subscriptions_errors view I'm proposing is a view showing the
> > > details of error happening during logical replication. So I think a
> > > separate view or pg_stat_subscription view would be a more appropriate
> > > place.
> > >
> >
> > +1 for having these stats in pg_stat_subscription. Do we want to add
> > two columns (xact_commit: number of transactions successfully applied
> > in this subscription, xact_rollback: number of transactions that have
> > been rolled back in this subscription)
>
> Sounds good. We might want to have separate counters for the number of
> transactions failed due to an error and transactions rolled back by
> stream_abort.
>

I was trying to think based on similar counters in pg_stat_database
but if you think there is a value in showing errored and actual
rollbacked transactions separately then we can do that but how do you
think one can make use of it?

-- 
With Regards,
Amit Kapila.