Horton

Re: Logical replication timeout problem

Amit Kapila <amit.kapila16@gmail.com>

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From: Amit Kapila <amit.kapila16@gmail.com>
To: Fabrice Chapuis <fabrice636861@gmail.com>
Cc: Tang, Haiying/唐 海英 <tanghy.fnst@fujitsu.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2022-01-12T10:54:21Z
Lists: pgsql-hackers 
On Tue, Jan 11, 2022 at 8:13 PM Fabrice Chapuis <fabrice636861@gmail.com>
wrote:

> Can you explain why you think this will help in solving your current
> problem?
>
> Indeed your are right this function won't help, we have to look elsewhere.
>
> It is still not clear to me why the problem happened? IIUC, after
> restoring 4096 changes from snap files, we send them to the subscriber, and
> then apply worker should apply those one by one. Now, is it taking one
> minute to restore 4096 changes due to which apply worker is timed out?
>
> Now I can easily reproduce the problem.
> In a first phase, snap files are generated and stored in pg_replslot. This
> process end when1420 files are present in pg_replslots (this is in relation
> with statements that must be replayed from WAL). In the pg_stat_replication
> view, the state field is set to *catchup*.
> In a 2nd phase, the snap files must be decoded. However after one minute
> (wal_receiver_timeout parameter set to 1 minute) the worker process stop
> with a timeout.
>
>
What exactly do you mean by the first and second phase in the above
description?

-- 
With Regards,
Amit Kapila.

Commits

  1. Fix the logical replication timeout during large DDLs.

  2. Fix the logical replication timeout during large transactions.

  3. Rethink the delay-checkpoint-end mechanism in the back-branches.

  4. Revert "Logical decoding of sequences"

  5. Skip empty transactions for logical replication.

  6. Allow specifying column lists for logical replication

  7. Add decoding of sequences to built-in replication

  8. Fix ABI break introduced by commit 4daa140a2f.

  9. Lag tracking for logical replication