On Tue, Mar 17, 2026 at 11:00 AM Fujii Masao <[email protected]> wrote: > > On Mon, Mar 16, 2026 at 9:26 AM Shinya Kato <[email protected]> wrote: > > Thank you for the v4 patch. I think this approach is better than mine. > > I tested the patch and confirmed that the issue no longer reproduces > > with physical replication. However, with logical replication, the lag > > columns in pg_stat_replication still show NULL periodically at > > wal_receiver_status_interval, since send_feedback() in worker.c can > > still send duplicate positions. > > I was thinking that if a feedback message triggered by > wal_receiver_status_interval has the same LSNs as the previous message, > it's expected for the lag columns to become NULL. But you see it differently, > don't you? Sorry, I failed to understand your point...
Sorry for the confusion. I ran a script inserting one row every 0.5 seconds under logical replication and confirmed that NULL still appears in the lag columns even while replication is actively running. I was initially mistaken that this was tied to wal_receiver_status_interval timing — that turned out to be unrelated. I haven't had time to investigate further, but my current impression is that the existing approach may not be sufficient for logical replication. -- Best regards, Shinya Kato NTT OSS Center
