Re: speed up a logical replica setup

Hi,

On Wed, 6 Dec 2023 at 12:53, Euler Taveira <euler@eulerto.com> wrote:
>
> On Thu, Nov 9, 2023, at 8:12 PM, Michael Paquier wrote:
>
> On Thu, Nov 09, 2023 at 03:41:53PM +0100, Peter Eisentraut wrote:
> > On 08.11.23 00:12, Michael Paquier wrote:
> >> - Should the subdirectory pg_basebackup be renamed into something more
> >> generic at this point?  All these things are frontend tools that deal
> >> in some way with the replication protocol to do their work.  Say
> >> a replication_tools?
> >
> > Seems like unnecessary churn.  Nobody has complained about any of the other
> > tools in there.
>
> Not sure.  We rename things across releases in the tree from time to
> time, and here that's straight-forward.
>
>
> Based on this discussion it seems we have a consensus that this tool should be
> in the pg_basebackup directory. (If/when we agree with the directory renaming,
> it could be done in a separate patch.) Besides this move, the v3 provides a dry
> run mode. It basically executes every routine but skip when should do
> modifications. It is an useful option to check if you will be able to run it
> without having issues with connectivity, permission, and existing objects
> (replication slots, publications, subscriptions). Tests were slightly improved.
> Messages were changed to *not* provide INFO messages by default and --verbose
> provides INFO messages and --verbose --verbose also provides DEBUG messages. I
> also refactored the connect_database() function into which the connection will
> always use the logical replication mode. A bug was fixed in the transient
> replication slot name. Ashutosh review [1] was included. The code was also indented.
>
> There are a few suggestions from Ashutosh [2] that I will reply in another
> email.
>
> I'm still planning to work on the following points:
>
> 1. improve the cleanup routine to point out leftover objects if there is any
>    connection issue.
> 2. remove the physical replication slot if the standby is using one
>    (primary_slot_name).
> 3. provide instructions to promote the logical replica into primary, I mean,
>    stop the replication between the nodes and remove the replication setup
>    (publications, subscriptions, replication slots). Or even include another
>    action to do it. We could add both too.
>
> Point 1 should be done. Points 2 and 3 aren't essential but will provide a nice
> UI for users that would like to use it.
>
>
> [1] https://postgr.es/m/CAExHW5sCAU3NvPKd7msScQKvrBN-x_AdDQD-ZYAwOxuWG%3Doz1w%40mail.gmail.com
> [2] https://postgr.es/m/CAExHW5vHFemFvTUHe+7XWphVZJxrEXz5H3dD4UQi7CwmdMJQYg@mail.gmail.com
>

The changes in the file 'src/tools/msvc/Mkvcbuild.pm' seems
unnecessary as the folder 'msvc' is removed due to the commit [1].


To review the changes, I did 'git reset --hard' to the commit previous
to commit [1].
I tried to build the postgres on my Windows machine using two methods:
i. building using Visual Studio
ii. building using Meson

When I built the code using Visual Studio, on installing postgres,
pg_subscriber binary was not created.
But when I built the code using Meson, on installing postgres,
pg_subscriber binary was created.
Is this behaviour intentional?

[1] https://github.com/postgres/postgres/commit/1301c80b2167feb658a738fa4ceb1c23d0991e23

Thanks and Regards,
Shlok Kyal