Re: Replication slot stats misgivings

vignesh C <vignesh21@gmail.com>

From: vignesh C <vignesh21@gmail.com>

To: Amit Kapila <amit.kapila16@gmail.com>

Cc: Masahiko Sawada <sawada.mshk@gmail.com>, Andres Freund <andres@anarazel.de>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>

Date: 2021-04-12T12:16:37Z

Lists: pgsql-hackers

Attachments

v8-0001-Changed-char-datatype-to-NameData-datatype-for-sl.patch (text/x-patch) patch v8-0001
v8-0002-Use-HTAB-for-replication-slot-statistics.patch (text/x-patch) patch v8-0002
v8-0003-Added-total-txns-and-total-txn-bytes-to-replicati.patch (text/x-patch) patch v8-0003
v8-0004-Added-tests-for-verification-of-logical-replicati.patch (text/x-patch) patch v8-0004
v8-0005-Test-where-there-are-more-replication-slot-statis.patch (text/x-patch) patch v8-0005

On Mon, Apr 12, 2021 at 4:46 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Sat, Apr 10, 2021 at 6:51 PM vignesh C <vignesh21@gmail.com> wrote:
> >
>
> Thanks, 0001 and 0002 look good to me. I have a minor comment for 0002.
>
> <entry role="catalog_table_entry"><para role="column_definition">
> +        <structfield>total_bytes</structfield><type>bigint</type>
> +       </para>
> +       <para>
> +        Amount of decoded transactions data sent to the decoding output plugin
> +        while decoding the changes from WAL for this slot. This can be used to
> +        gauge the total amount of data sent during logical decoding.
>
> Can we slightly extend it to say something like: Note that this
> includes the bytes streamed and or spilled. Similarly, we can extend
> it for total_txns.
>

Thanks for the comments, the comments are fixed in the v8 patch attached.
Thoughts?

Regards,
Vignesh

Commits

Doc: Update logical decoding stats information.
- 0c6b92d9c6fb 14.0 landed
Fix tests for replication slots stats.
- fc69509131c3 14.0 landed
Update replication statistics after every stream/spill.
- 592f00f8dec6 14.0 landed
Fix the computation of slot stats for 'total_bytes'.
- 205f466282be 14.0 landed
Another try to fix the test case added by commit f5fc2f5b23.
- 51ef9173030c 14.0 landed
Use HTAB for replication slot statistics.
- 3fa17d37716f 14.0 landed
Fix test case added by commit f5fc2f5b23.
- c64dcc7fee5f 14.0 landed
Add information of total data processed to replication slot stats.
- f5fc2f5b23d1 14.0 landed
Use NameData datatype for slotname in stats.
- cca57c1d9bf7 14.0 landed