Re: pg_stat_progress_basebackup - progress reporting for pg_basebackup, in the server side

On Mon, Feb 17, 2020 at 10:00 PM Fujii Masao
<masao(dot)fujii(at)oss(dot)nttdata(dot)com> wrote:
> On 2020/02/06 11:07, Amit Langote wrote:
> > On Thu, Feb 6, 2020 at 9:51 AM Kyotaro Horiguchi <horikyota(dot)ntt(at)gmail(dot)com> wrote:
> >> I thought of "establishing checkpoint" or "running a checkpoint" as
> >> other candidates.
> >
> > Okay, I understand. I am fine with "running checkpoint", although I
> > think "waiting for checkpoint" isn't totally wrong either.
>
> Yeah, but if "waiting for XXX" sounds a bit confusing to some people,
> I'm OK to back to "waiting for XXX to finish" that you originally
> proposed.
>
> Attached the updated version of the patch. This patch uses the following
> descriptions of the phases.
>
> waiting for checkpoint to finish
> estimating backup size
> streaming database files
> waiting for wal archiving to finish
> transferring wal files

Thanks for the new patch.

I noticed that there is missing </para> tag in the documentation changes:

+ <row>
+ <entry><literal>waiting for checkpoint to finish</literal></entry>
+ <entry>
+ The WAL sender process is currently performing
+ <function>pg_start_backup</function> to set up for
+ taking a base backup, and waiting for backup start
+ checkpoint to finish.
+ </entry>
+ <row>

There should be a </row> between </entry> and <row> at the end of the
hunk shown above.

Sorry for not saying it before, but the following text needs revisiting:

+ <para>
+ Whenever <application>pg_basebackup</application> is taking a base
+ backup, the <structname>pg_stat_progress_basebackup</structname>
+ view will contain a row for each WAL sender process that is currently
+ running <command>BASE_BACKUP</command> replication command
+ and streaming the backup.

I understand that you wrote "Whenever pg_basebackup is taking a
backup...", because description of other views contains a similar
starting line. But, it may not only be pg_basebackup that would be
served by this view, no? It could be any tool that speaks Postgres'
replication protocol and thus be able to send a BASE_BACKUP command.
If that is correct, I would write something like "When an application
is taking a backup" or some such without specific reference to
pg_basebackup. Thoughts?

Thanks,
Amit