Re: Initial COPY of Logical Replication is too slow

On Tue, Mar 31, 2026 at 5:07 AM Zhijie Hou (Fujitsu)
<houzj(dot)fnst(at)fujitsu(dot)com> wrote:
>
> On Tuesday, March 31, 2026 5:36 PM Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> wrote:
> >
> > On Wed, Mar 25, 2026 at 2:19 PM Peter Smith <smithpb2250(at)gmail(dot)com>
> > wrote:
> > >
> > > There are many return points, and most of those "if" blocks cannot
> > > fall through (they return).
> > >
> > > I found it slightly difficult to read the code because I kept having
> > > to think, "OK, if we reached here, it means pubviaroot must be false,"
> > > or "OK, if we reached this far, then puballtables must be false, and
> > > pubviaroot must be false," etc.
> > >
> >
> > I can't say exactly why, but I find it difficult to read this function. So, I share
> > your concerns about the code of this function.
> > Because of its complexity it is difficult to ascertain that the functionality is
> > correct or we missed something. Also, considering it is correct today, in its
> > current form, it may become difficult to enhance it in future.
> >
>
> I attempted to refactor the code a bit based on my preferred style, as shown in
> the attachment. While the number of return points couldn't be reduced, I tried
> to eliminate if-else branches where possible. Sharing this top-up patch as a
> reference for an alternative style that reduces code size.
>

Thanks. It looks like a good refactoring! I'd prefer to free the
ancestors list to avoid memory leak.

I've attached the patch that incorporated all comments I got so far.
Feedback is very welcome.

Regards,

--
Masahiko Sawada
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