Re: Add sub-transaction overflow status in pg_stat_activity - Mailing list pgsql-hackers

From Dilip Kumar
Subject Re: Add sub-transaction overflow status in pg_stat_activity
Date
Msg-id CAFiTN-sG6uuRJaBBU+NaTRu6oefKtcvfKDyt+Uyvmb9B+YafuQ@mail.gmail.com
Whole thread Raw
In response to Re: Add sub-transaction overflow status in pg_stat_activity  (Justin Pryzby <pryzby@telsasoft.com>)
List pgsql-hackers
On Tue, Dec 7, 2021 at 11:11 AM Justin Pryzby <pryzby@telsasoft.com> wrote:

Thanks for the review I will work on these comments.

> > +      <entry role="catalog_table_entry"><para role="column_definition">
> > +       <structfield>subxact_count</structfield> <type>xid</type>
> > +      </para>
> > +      <para>
> > +       The current backend's active subtransactions count.
>
> subtransaction (no s)
>
> > +       Set to true if current backend's subtransaction cache is overflowed.
>
> Say "has overflowed"
>
> > +             if (local_beentry->subxact_count > 0)
> > +             {
> > +                     values[30] = local_beentry->subxact_count;
> > +                     values[31] = local_beentry->subxact_overflowed;
> > +             }
> > +             else
> > +             {
> > +                     nulls[30] = true;
> > +                     nulls[31] = true;
> > +             }
>
> Why is the subxact count set to NULL instead of zero ?

> You added this to pg_stat_activity, which already has a lot of fields.
> We talked a few months ago about not adding more fields that weren't commonly
> used.
>
https://www.postgresql.org/message-id/flat/20210426191811.sp3o77doinphyjhu%40alap3.anarazel.de#d96d0a116f0344301eead2676ea65b2e
>
> Since I think this field is usually not interesting to most users of
> pg_stat_activity, maybe this should instead be implemented as a function like
> pg_backend_get_subxact_status(pid).
>
> People who want to could use it like:
> SELECT * FROM pg_stat_activity psa, pg_backend_get_subxact_status(pid) sub;

Yeah, this is a valid point, I will change this accordingly.

-- 
Regards,
Dilip Kumar
EnterpriseDB: http://www.enterprisedb.com



pgsql-hackers by date:

Previous
From: Amit Kapila
Date:
Subject: Re: Alter all tables in schema owner fix
Next
From: Dilip Kumar
Date:
Subject: Re: Add sub-transaction overflow status in pg_stat_activity