Re: confirmed_flush_lsn shows LSN of the data that has not yet been received by the logical subscriber.
Ashutosh Sharma <ashu.coek88@gmail.com>
From: Ashutosh Sharma <ashu.coek88@gmail.com>
To: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>,
Andres Freund <andres@anarazel.de>
Date: 2022-09-19T14:39:11Z
Lists: pgsql-hackers
Attachments
- fix-doc-for-confirmed_flush_lsn.patch (text/x-patch) patch
On Mon, Sep 19, 2022 at 5:24 PM Ashutosh Bapat <ashutosh.bapat.oss@gmail.com> wrote: > > On Mon, Sep 19, 2022 at 1:43 PM Ashutosh Sharma <ashu.coek88@gmail.com> wrote: > > > > On Fri, Sep 9, 2022 at 5:36 PM Ashutosh Bapat > > <ashutosh.bapat.oss@gmail.com> wrote: > > > > > > On Thu, Sep 8, 2022 at 8:32 PM Ashutosh Sharma <ashu.coek88@gmail.com> wrote: > > > > > > > > On Thu, Sep 8, 2022 at 6:23 PM Ashutosh Bapat > > > > <ashutosh.bapat.oss@gmail.com> wrote: > > > > > > > > > > On Thu, Sep 8, 2022 at 4:14 PM Ashutosh Sharma <ashu.coek88@gmail.com> wrote: > > > Can you please point to the documentation. > > > > > > > AFAIU there is just one documentation. Here is the link for it: > > > > https://www.postgresql.org/docs/current/view-pg-replication-slots.html > > Thanks. Description of confirmed_flush_lsn is "The address (LSN) up to > which the logical slot's consumer has confirmed receiving data. Data > older than this is not available anymore. NULL for physical slots." > The second sentence is misleading. AFAIU, it really should be "Data > corresponding to the transactions committed before this LSN is not > available anymore". WAL before restart_lsn is likely to be removed but > WAL with LSN higher than restart_lsn is preserved. This correction > makes more sense because of the third sentence. > Thanks for the clarification. Attached is the patch with the changes. Please have a look. -- With Regards, Ashutosh Sharma.
Commits
-
Doc: Improve the description of confirmed_flush_lsn in pg_replication_slots.
- 3e77b2eb3466 16.0 landed