Re: [PATCH] Reuse Workers and Replication Slots during Logical Replication

On Tue, Jul 11, 2023 at 12:31 AM Melih Mutlu <m(dot)melihmutlu(at)gmail(dot)com> wrote:
>
> Hi,
>
> Hayato Kuroda (Fujitsu) <kuroda(dot)hayato(at)fujitsu(dot)com>, 6 Tem 2023 Per,
> 12:47 tarihinde şunu yazdı:
> >
> > Dear Melih,
> >
> > > Thanks for the 0003 patch. But it did not work for me. Can you create
> > > a subscription successfully with patch 0003 applied?
> > > I get the following error: " ERROR: table copy could not start
> > > transaction on publisher: another command is already in progress".
> >
> > You got the ERROR when all the patches (0001-0005) were applied, right?
> > I have focused on 0001 and 0002 only, so I missed something.
> > If it was not correct, please attach the logfile and test script what you did.
>
> Yes, I did get an error with all patches applied. But with only 0001
> and 0002, your version seems like working and mine does not.
> What do you think about combining 0002 and 0003? Or should those stay separate?
>

Even if patches 0003 and 0002 are to be combined, I think that should
not happen until after the "reuse" design is confirmed which way is
best.

e.g. IMO it might be easier to compare the different PoC designs for
patch 0002 if there is no extra logic involved.

PoC design#1 -- each tablesync decides for itself what to do next
after it finishes
PoC design#2 -- reuse tablesync using a "pool" of available workers

------
Kind Regards,
Peter Smith.
Fujitsu Australia