Re: Asynchronous Append on postgres_fdw nodes. - Mailing list pgsql-hackers

From Etsuro Fujita
Subject Re: Asynchronous Append on postgres_fdw nodes.
Date
Msg-id CAPmGK16PzmShES=4jH+usW+8SK3qduevob9TVw_m=ibWFOGcZg@mail.gmail.com
Whole thread Raw
In response to Re: Asynchronous Append on postgres_fdw nodes.  (Stephen Frost <sfrost@snowman.net>)
Responses Re: Asynchronous Append on postgres_fdw nodes.  (Etsuro Fujita <etsuro.fujita@gmail.com>)
List pgsql-hackers
On Fri, May 7, 2021 at 2:12 AM Stephen Frost <sfrost@snowman.net> wrote:
> I'd suggest the language point out that it's not actually possible to do
> otherwise, since they all need to be part of the same transaction.
>
> Without that, it looks like we're just missing a trick somewhere and
> someone might think that they could improve PG to open multiple
> connections to the same remote server to execute them in parallel.

Agreed.

> Maybe:
>
> In order to ensure that the data being returned from a foreign server
> is consistent, postgres_fdw will only open one connection for a given
> foreign server and will run all queries against that server sequentially
> even if there are multiple foreign tables involved.  In such a case, it
> may be more performant to disable this option to eliminate the overhead
> associated with running queries asynchronously.

Ok, I’ll merge this into the next version.

Thanks!

Best regards,
Etsuro Fujita



pgsql-hackers by date:

Previous
From: Andrew Dunstan
Date:
Subject: Re: Anti-critical-section assertion failure in mcxt.c reached by walsender
Next
From: Etsuro Fujita
Date:
Subject: Re: Asynchronous Append on postgres_fdw nodes.