Horton

Re: Replication slot stats misgivings

Amit Kapila <amit.kapila16@gmail.com>

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From: Amit Kapila <amit.kapila16@gmail.com>
To: Masahiko Sawada <sawada.mshk@gmail.com>
Cc: Andres Freund <andres@anarazel.de>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Kyotaro HORIGUCHI <horiguchi.kyotaro@lab.ntt.co.jp>
Date: 2021-04-06T05:52:47Z
Lists: pgsql-hackers 
On Mon, Mar 22, 2021 at 9:55 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> On Sat, Mar 20, 2021 at 3:52 AM Andres Freund <andres@anarazel.de> wrote:
> >
> >
> > - PgStat_ReplSlotStats etc use slotname[NAMEDATALEN]. Why not just NameData?
>
> That's because we followed other definitions in pgstat.h that use
> char[NAMEDATALEN]. I'm okay with using NameData.
>

I see that at many places in code we use char[NAMEDATALEN] for names.
However, for slotname, we use NameData, see:
typedef struct ReplicationSlotPersistentData
{
/* The slot's identifier */
NameData name;

So, it will be better to use the same for pgstat purposes as well. In
other words, I also agree with this decision and I see that Vignesh
has already used NameData for slot_name in his recent patch.

-- 
With Regards,
Amit Kapila.

Commits

  1. Doc: Update logical decoding stats information.

  2. Fix tests for replication slots stats.

  3. Update replication statistics after every stream/spill.

  4. Fix the computation of slot stats for 'total_bytes'.

  5. Another try to fix the test case added by commit f5fc2f5b23.

  6. Use HTAB for replication slot statistics.

  7. Fix test case added by commit f5fc2f5b23.

  8. Add information of total data processed to replication slot stats.

  9. Use NameData datatype for slotname in stats.