Horton

Re: speed up a logical replica setup

Junwang Zhao <zhjwpku@gmail.com>

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From: Junwang Zhao <zhjwpku@gmail.com>
To: Euler Taveira <euler@eulerto.com>
Cc: "kuroda.hayato@fujitsu.com" <kuroda.hayato@fujitsu.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>, Shlok Kyal <shlok.kyal.oss@gmail.com>, vignesh C <vignesh21@gmail.com>, Michael Paquier <michael@paquier.xyz>, Peter Eisentraut <peter@eisentraut.org>, Andres Freund <andres@anarazel.de>, Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>
Date: 2024-01-14T01:42:46Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. pg_createsubscriber: Remove obsolete comment

  2. pg_createsubscriber: Fix an unpredictable recovery wait time.

  3. Fix unstable test in 040_pg_createsubscriber.

  4. Fix the testcase introduced in commit 81d20fbf7a.

  5. Further weaken new pg_createsubscriber test on Windows.

  6. Temporarily(?) weaken new pg_createsubscriber test on Windows.

  7. Make pg_createsubscriber warn if publisher has two-phase commit enabled.

  8. Make pg_createsubscriber more wary about quoting connection parameters.

  9. pg_createsubscriber: Remove failover replication slots on subscriber

  10. pg_createsubscriber: Remove replication slot check on primary

  11. pg_createsubscriber: Only --recovery-timeout controls the end of recovery process

  12. pg_createsubscriber: creates a new logical replica from a standby server

  13. Add some const decorations

  14. Add option force_initdb to PostgreSQL::Test::Cluster:init()

  15. Remove MSVC scripts

Hi Euler,

On Fri, Jan 12, 2024 at 6:16 AM Euler Taveira <euler@eulerto.com> wrote:
>
> On Thu, Jan 11, 2024, at 9:18 AM, Hayato Kuroda (Fujitsu) wrote:
>
> I have been concerned that the patch has not been tested by cfbot due to the
> application error. Also, some comments were raised. Therefore, I created a patch
> to move forward.
>
>
> Let me send an updated patch to hopefully keep the CF bot happy. The following
> items are included in this patch:
>
> * drop physical replication slot if standby is using one [1].
> * cleanup small changes (copyright, .gitignore) [2][3]
> * fix getopt_long() options [2]
> * fix format specifier for some messages
> * move doc to Server Application section [4]
> * fix assert failure
> * ignore duplicate database names [2]
> * store subscriber server log into a separate file
> * remove MSVC support
>
> I'm still addressing other reviews and I'll post another version that includes
> it soon.
>
> [1] https://www.postgresql.org/message-id/e02a2c17-22e5-4ba6-b788-de696ab74f1e%40app.fastmail.com
> [2] https://www.postgresql.org/message-id/CALDaNm1joke42n68LdegN5wCpaeoOMex2EHcdZrVZnGD3UhfNQ%40mail.gmail.com
> [3] https://www.postgresql.org/message-id/TY3PR01MB98895BA6C1D72CB8582CACC4F5682%40TY3PR01MB9889.jpnprd01.prod.outlook.com
> [4] https://www.postgresql.org/message-id/TY3PR01MB988978C7362A101927070D29F56A2%40TY3PR01MB9889.jpnprd01.prod.outlook.com
>

+ <refnamediv>
+  <refname>pg_subscriber</refname>
+  <refpurpose>create a new logical replica from a standby server</refpurpose>
+ </refnamediv>
I'm a bit confused about this wording because we are converting a standby
to a logical replica but not creating a new logical replica and leaving the
standby as is. How about:

<refpurpose>convert a standby replica to a logical replica</refpurpose>

+  <para>
+   The <application>pg_subscriber</application> should be run at the target
+   server. The source server (known as publisher server) should accept logical
+   replication connections from the target server (known as subscriber server).
+   The target server should accept local logical replication connection.
+  </para>

What is *local logical replication*? I can't find any clue in the patch, can you
give me some hint?


>
> --
> Euler Taveira
> EDB   https://www.enterprisedb.com/
>


-- 
Regards
Junwang Zhao