Horton

RE: speed up a logical replica setup

Hayato Kuroda (Fujitsu) <kuroda.hayato@fujitsu.com>

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From: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>
To: 'Shubham Khanna' <khannashubham1197@gmail.com>
Cc: Euler Taveira <euler@eulerto.com>, Fabrízio de Royes Mello <fabriziomello@gmail.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>, 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>, Shlok Kyal <shlok.kyal.oss@gmail.com>
Date: 2024-02-06T08:44:44Z
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

Attachments

Dear Shubham,

Thanks for testing our codes!

> While reviewing the v15 patches I discovered that subscription
> connection string has added a lot of options which are not required
> now:
> v15-0001
> postgres=# select subname, subconninfo from pg_subscription;
>             subname            |               subconninfo
> -------------------------------+------------------------------------------
> pg_createsubscriber_5_1867633 | host=localhost port=5432 dbname=postgres
> (1 row)
> 
> 
> 
> v15-0001+0002+0003
> postgres=# select subname, subconninfo from pg_subscription;
>             subname            |
> 
>       subconninfo
> 
> 
> 
> -------------------------------+--------------------------------------------------
> ----------------------
> ----------------------------------------------------------------------------------
> ----------------------
> ----------------------------------------------------------------------------------
> ----------------------
> ------------------------------
> pg_createsubscriber_5_1895366 | user=shubham
> passfile='/home/shubham/.pgpass' channel_binding=prefer ho
> st=127.0.0.1 port=5432 sslmode=prefer sslcompression=0
> sslcertmode=allow sslsni=1 ssl_min_protocol_versi
> on=TLSv1.2 gssencmode=disable krbsrvname=postgres gssdelegation=0
> target_session_attrs=any load_balance_
> hosts=disable dbname=postgres
> (1 row)
> 
> 
> Here, we can see that channel_binding, sslmode, sslcertmode, sslsni,
> gssencmode, krbsrvname, etc are getting included. This does not look
> intentional, we should keep the subscription connection same as in
> v15-0001.

You should attach the script the reproducer. I suspected you used pg_basebackup
-R command for setting up the standby. In this case, it is intentional.
These settings are not caused by the pg_createsubscriber, done by pg_basebackup.
If you set primary_conninfo manually like attached, these settings would not appear.

As the first place, listed options (E.g., passfile, channel_binding, sslmode,
sslcompression, sslcertmode, etc...) were set when you connect to the database
via libpq functions. PQconninfoOptions in fe-connect.c lists parameters and
their default value.

v15-0003 reuses the primary_conninfo for subconninfo attribute. primary_conninfo
is set by pg_basebackup specified with '-R' option.
The content is built in GenerateRecoveryConfig(), which bypass parameters from
PQconninfo(). This function returns all the libpq connection parameters even if
it is set as default. So primary_conninfo looks longer.

I don't think this works wrongly. Users still can set an arbitrary connection
string as primary_conninfo. You just use longer string unintentionally.

Best Regards,
Hayato Kuroda
FUJITSU LIMITED
https://www.fujitsu.com/