Horton

Re: speed up a logical replica setup

Euler Taveira <euler@eulerto.com>

View thread
From: "Euler Taveira" <euler@eulerto.com>
To: "Amit Kapila" <amit.kapila16@gmail.com>
Cc: "vignesh C" <vignesh21@gmail.com>, "Michael Paquier" <michael@paquier.xyz>, "Peter Eisentraut" <peter@eisentraut.org>, pgsql-hackers@lists.postgresql.org, "Andres Freund" <andres@anarazel.de>, "Ashutosh Bapat" <ashutosh.bapat.oss@gmail.com>
Date: 2024-01-04T15:57:15Z
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 Thu, Jan 4, 2024, at 3:05 AM, Amit Kapila wrote:
> Won't it be a better user experience that after setting up the target
> server as a logical replica (subscriber), it started to work
> seamlessly without user intervention?

If we have an option to control the replication slot removal (default is on),
it seems a good UI. Even if the user decides to disable the replication slot
removal, it should print a message saying that these replication slots can
cause WAL retention.

> > The initial version had an option to stop the subscriber. I decided to
> > remove the option and stop the subscriber by default mainly because (1) it is
> > an extra step to start the server (another point is that the WAL retention
> > doesn't happen due to additional (synchronized?) replication slots on
> > subscriber -- point 2). It was a conservative choice. If point 2 isn't an
> > issue, imo point 1 is no big deal.
> >
> 
> By point 2, do you mean to have a check for "max replication slots"?
> It so, the one possibility is to even increase that config, if the
> required max_replication_slots is low.

By point 2, I mean WAL retention (sentence inside parenthesis).


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