Re: Logical replication timeout problem - Mailing list pgsql-hackers

From Ashutosh Bapat
Subject Re: Logical replication timeout problem
Date
Msg-id CAExHW5vhjqMvpVNWoMxiPE_5-3hjYToufeoKWapx0J+mm2WKAw@mail.gmail.com
Whole thread Raw
In response to RE: Logical replication timeout problem  ("wangw.fnst@fujitsu.com" <wangw.fnst@fujitsu.com>)
Responses Re: Logical replication timeout problem
List pgsql-hackers
On Wed, Jan 18, 2023 at 1:49 PM wangw.fnst@fujitsu.com
<wangw.fnst@fujitsu.com> wrote:
>
> On Wed, Jan 18, 2023 at 13:29 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> > On Tue, Jan 17, 2023 at 6:41 PM Ashutosh Bapat
> > <ashutosh.bapat.oss@gmail.com> wrote:
> > >
> > > On Tue, Jan 17, 2023 at 3:34 PM Amit Kapila <amit.kapila16@gmail.com> wrote:
> > >
> > > > >
> > > > > I am a bit worried about the indirections that the wrappers and hooks
> > > > > create. Output plugins call OutputPluginUpdateProgress() in callbacks
> > > > > but I don't see why  ReorderBufferProcessTXN() needs a callback to
> > > > > call OutputPluginUpdateProgress.
> > > > >
> > > >
> > > > Yeah, I think we can do it as we are doing the previous approach but
> > > > we need an additional wrapper (update_progress_cb_wrapper()) as the
> > > > current patch has so that we can add error context information. This
> > > > is similar to why we have a wrapper for all other callbacks like
> > > > change_cb_wrapper.
> > > >
> > >
> > > Ultimately OutputPluginUpdateProgress() will be called - which in turn
> > > will call ctx->update_progress.
> > >
> >
> > No, update_progress_cb_wrapper() should directly call
> > ctx->update_progress(). The key reason to have a
> > update_progress_cb_wrapper() is that it allows us to add error context
> > information (see the usage of output_plugin_error_callback).
>
> I think it makes sense. This also avoids the need for every output plugin to
> implement the callback. So I tried to improve the patch based on this approach.
>
> And I tried to add some comments for this new callback to distinguish it from
> ctx->update_progress.

Comments don't help when using cscope or some such code browsing tool.
Better to use a different variable name.

-- 
Best Wishes,
Ashutosh Bapat



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