Horton

Re: speed up a logical replica setup

Peter Eisentraut <peter@eisentraut.org>

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From: Peter Eisentraut <peter@eisentraut.org>
To: Amit Kapila <amit.kapila16@gmail.com>
Cc: Euler Taveira <euler@eulerto.com>, Shlok Kyal <shlok.kyal.oss@gmail.com>, "kuroda.hayato@fujitsu.com" <kuroda.hayato@fujitsu.com>, Tomas Vondra <tomas.vondra@enterprisedb.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>, Michael Paquier <michael@paquier.xyz>, Andres Freund <andres@anarazel.de>, Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>, Fabrízio de Royes Mello <fabriziomello@gmail.com>, vignesh C <vignesh21@gmail.com>
Date: 2024-03-19T11:56:10Z
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

On 19.03.24 08:05, Amit Kapila wrote:
> On Mon, Mar 18, 2024 at 7:22 PM Peter Eisentraut <peter@eisentraut.org> wrote:
>>
>> In check_subscriber(): All these permissions checks seem problematic
>> to me.  We shouldn't reimplement our own copy of the server's
>> permission checks.  The server can check the permissions.  And if the
>> permission checking in the server ever changes, then we have
>> inconsistencies to take care of.  Also, the error messages "permission
>> denied" are inappropriate, because we are not doing the actual thing.
>> Maybe we want to do a dry-run for the benefit of the user, but then we
>> should do the actual thing, like try to create a replication slot, or
>> whatever.  But I would rather just remove all this, it seems too
>> problematic.
>>
> 
> If we remove all the checks then there is a possibility that we can
> fail later while creating the actual subscription. For example, if
> there are not sufficient max_replication_slots, then it is bound to
> fail in the later steps which would be a costlier affair because by
> that time the standby would have been promoted and the user won't have
> any way to move forward but to re-create standby and then use this
> tool again. I think here the patch tries to mimic pg_upgrade style
> checks where we do some pre-checks.

I think checking for required parameter settings is fine.  My concern is 
with the code before that, that does 
pg_has_role/has_database_privilege/has_function_privilege.