Re: pg_upgrade: optimize replication slot caught-up check

On Tue, Jan 27, 2026 at 12:04 PM Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
>
> On Tue, Jan 27, 2026 at 3:59 AM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> >
> > On Fri, Jan 23, 2026 at 2:04 AM Masahiko Sawada <sawada(dot)mshk(at)gmail(dot)com> wrote:
> > >
> >
> > I haven't reviewed v7 in detail but while glancing, I noticed a few
> > minor comments:
> >
> > 1.
> > + * Returns the last LSN decodable WAL record's LSN if found, otherwise
> > + * returns InvalidXLogRecPtr.
> > */
> > -bool
> > -LogicalReplicationSlotHasPendingWal(XLogRecPtr end_of_wal)
> > +XLogRecPtr
> > +LogicalReplicationSlotHasPendingWal(XLogRecPtr end_of_wal,
> > + XLogRecPtr scan_cutoff_lsn)
> >
> > The function name suggests that it will return boolean (due to 'Has'
> > in its name) but after this change that is not true.
> >
> > 2.
> > We
> > + * also use the maximum confirmed_flush_lsn as an early scan
> > + * cutoff; finding a decodable WAL record beyond this point
> > + * implies that no slot has caught up.
> > + *
> >
> > In this comment, it is not clear if the maximum confirmed_flush_lsn is
> > among all logical slots (of current database) or what?
> >
>
> Thank you for the comments!
>
> I've incorporated these comments I got so far.
>
> Amit, are you planning to review the patch in detail? If so, I want to
> incorporate comments before the push.
>

I missed fixing one place. Attached the new version.

Regards,

--
Masahiko Sawada
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