Re: Performance degradation on concurrent COPY into a single relation in PG16.

Hi,

On 2023-07-03 11:55:13 +0900, Masahiko Sawada wrote:
> While testing PG16, I observed that in PG16 there is a big performance
> degradation in concurrent COPY into a single relation with 2 - 16
> clients in my environment. I've attached a test script that measures
> the execution time of COPYing 5GB data in total to the single relation
> while changing the number of concurrent insertions, in PG16 and PG15.
> Here are the results on my environment (EC2 instance, RHEL 8.6, 128
> vCPUs, 512GB RAM):

Gah, RHEL with its frankenkernels, the bane of my existance.

FWIW, I had extensively tested this with XFS, just with a newer kernel. Have
you tested this on RHEL9 as well by any chance?

Greetings,

Andres Freund