Re: POC: enable logical decoding when wal_level = 'replica' without a server restart

Amit Kapila <amit.kapila16@gmail.com>

From: Amit Kapila <amit.kapila16@gmail.com>

To: Masahiko Sawada <sawada.mshk@gmail.com>

Cc: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, Shlok Kyal <shlok.kyal.oss@gmail.com>, Bertrand Drouvot <bertranddrouvot.pg@gmail.com>, shveta malik <shveta.malik@gmail.com>, Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>

Date: 2025-09-15T02:55:12Z

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 →

Fix regression test failure when wal_level is set to minimal.
- 0de5f0d869d1 19 (unreleased) landed
Toggle logical decoding dynamically based on logical slot presence.
- 67c20979ce72 19 (unreleased) landed
Disallow server start with sync_replication_slots = on and wal_level < logical.
- 12da45742cfd 19 (unreleased) cited

On Fri, Sep 12, 2025 at 11:18 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> On Thu, Sep 11, 2025 at 9:08 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> >
>
> > For the shutdown sequence, can't we think of resetting effective_wal
> > after a restart?
>
> Does it mean that effective_wal_level keeps 'logical' until the next
> server starts?
>

Yes, IIUC, effective_wal_level is anyway a derived value based on
current wal_level and presence of logical slots. So, what will be the
impact if it is not accurate at shutdown?

-- 
With Regards,
Amit Kapila.