Re: Excessive LOG messages from replication slot sync worker - Mailing list pgsql-hackers

From Fujii Masao
Subject Re: Excessive LOG messages from replication slot sync worker
Date
Msg-id CAHGQGwGQriuG1_y+oVNs=ux_RC_Ex8833T074FdZtrCRShqW3A@mail.gmail.com
Whole thread Raw
In response to Re: Excessive LOG messages from replication slot sync worker  (Fujii Masao <masao.fujii@gmail.com>)
Responses Re: Excessive LOG messages from replication slot sync worker
Re: Excessive LOG messages from replication slot sync worker
List pgsql-hackers
On Tue, Aug 12, 2025 at 7:14 PM Fujii Masao <masao.fujii@gmail.com> wrote:
>
> On Tue, Aug 12, 2025 at 6:25 PM Japin Li <japinli@hotmail.com> wrote:
> > I believe that the format %X-%X also works with sscanf(). However, to maintain
> > consistency, the format for sscanf() has been updated as well.
>
> Yes.
> Thanks for the patch!

With the patch, the excessive LOG messages from the replication slot sync
worker are gone. However, it still logged periodically, about two messages
every 30 seconds, for example:

2025-08-12 19:49:03.288 JST [sby][slotsync worker] LOG:  starting
logical decoding for slot "mysub"
2025-08-12 19:49:03.288 JST [sby][slotsync worker] DETAIL:  Streaming
transactions committing after 0/0FAD3940, reading WAL from 0/0D4C9CE8.
2025-08-12 19:49:03.289 JST [sby][slotsync worker] LOG:  logical
decoding found consistent point at 0/0D4C9CE8
2025-08-12 19:49:03.289 JST [sby][slotsync worker] DETAIL:  Logical
decoding will begin using saved snapshot.
2025-08-12 19:49:46.048 JST [sby][slotsync worker] LOG:  starting
logical decoding for slot "mysub"
2025-08-12 19:49:46.048 JST [sby][slotsync worker] DETAIL:  Streaming
transactions committing after 0/10A60230, reading WAL from 0/0FAEE120.
2025-08-12 19:49:46.049 JST [sby][slotsync worker] LOG:  logical
decoding found consistent point at 0/0FAEE120
2025-08-12 19:49:46.049 JST [sby][slotsync worker] DETAIL:  Logical
decoding will begin using saved snapshot.


I'm not sure these messages are useful for end users, and LOG might not be
the right level. They seem more like debug information, so should we consider
changing them to DEBUG, even with the proposed patch applied?

Regards,

--
Fujii Masao



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