Horton

Re: locking [user] catalog tables vs 2pc vs logical rep

Simon Riggs <simon.riggs@enterprisedb.com>

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From: Simon Riggs <simon.riggs@enterprisedb.com>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: "osumi.takamichi@fujitsu.com" <osumi.takamichi@fujitsu.com>, vignesh C <vignesh21@gmail.com>, Peter Smith <smithpb2250@gmail.com>, Andres Freund <andres@anarazel.de>, PostgreSQL-development <pgsql-hackers@postgresql.org>, Markus Wanner <markus.wanner@enterprisedb.com>
Date: 2021-06-17T13:34:14Z
Lists: pgsql-hackers 
On Thu, Jun 17, 2021 at 12:57 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
>
> On Thu, Jun 17, 2021 at 4:27 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> >
> > On Thu, Jun 17, 2021 at 8:41 AM osumi.takamichi@fujitsu.com
> > <osumi.takamichi@fujitsu.com> wrote:
> >
> > Pushed!
> >
> [Responding to Simon's comments]
>
> > If LOCK and TRUNCATE is advised against on all user catalog tables, why would CLUSTER only apply to pg_class? Surely its locking
> > level is the same as LOCK?
> >
>
> Cluster will also apply to all user catalog tables. I think we can
> extend it slightly as we have mentioned for Lock.

OK, good.

> > The use of "[user]" isn't fully explained, so it might not be clear that this applies to both Postgres catalog tables and any user tables
> > that have been nominated as catalogs. Probably worth linking to the "Capabilities" section to explain.
> >
>
> Sounds reasonable.
>
> > It would be worth coalescing the following sections into a single page, since they are just a few lines each:
> > Streaming Replication Protocol Interface
> > Logical Decoding SQL Interface
> > System Catalogs Related to Logical Decoding
> >
>
> I think this is worth considering but we might want to discuss this as
> a separate change/patch.

Makes sense.

Thanks

-- 
Simon Riggs                http://www.EnterpriseDB.com/

Commits

  1. Doc: Update caveats in synchronous logical replication.

  2. Document a few caveats in synchronous logical replication.

  3. Update the docs and comments for decoding of prepared xacts.

  4. Allow decoding at prepare time in ReorderBuffer.

  5. Documentation for logical decoding.