Re: Parallel Inserts in CREATE TABLE AS

On Fri, Oct 16, 2020 at 11:33 AM Luc Vlaming <luc(at)swarm64(dot)com> wrote:
>
> Really looking forward to this ending up in postgres as I think it's a
> very nice improvement.
>
> Whilst reviewing your patch I was wondering: is there a reason you did
> not introduce a batch insert in the destreceiver for the CTAS? For me
> this makes a huge difference in ingest speed as otherwise the inserts do
> not really scale so well as lock contention start to be a big problem.
> If you like I can make a patch to introduce this on top?
>

Thanks for your interest. You are right, we can get maximum
improvement if we have multi inserts in destreceiver for the CTAS on
the similar lines to COPY FROM command. I specified this point in my
first mail [1]. You may want to take a look at an already existing
patch [2] for multi inserts, I think there are some review comments to
be addressed in that patch. I would love to see the multi insert patch
getting revived.

[1] - https://www.postgresql.org/message-id/CALj2ACWFq6Z4_jd9RPByURB8-Y8wccQWzLf%2B0-Jg%2BKYT7ZO-Ug%40mail.gmail.com
[2] - https://www.postgresql.org/message-id/CAEET0ZG31mD5SWjTYsAt0JTLReOejPvusJorZ3kGZ1%3DN1AC-Fw%40mail.gmail.com

With Regards,
Bharath Rupireddy.
EnterpriseDB: http://www.enterprisedb.com