Re: Reference to - BUG #18349: ERROR: invalid DSA memory alloc request size 1811939328, CONTEXT: parallel worker

On Thu, Oct 17, 2024 at 9:12 PM Andrei Lepikhov <lepihov@gmail.com> wrote:
> Yeah, I misunderstood the meaning of the estimated_size variable. Your
> solution is more universal. Also, I confirm, it passes my synthetic  test.
> Also, it raises the immediate question: What if we have too many
> duplicates? Sometimes, in user complaints, I see examples where they,
> analysing the database's logical consistency, pass through millions of
> duplicates to find an unexpected value. Do we need a top memory
> consumption limit here? I recall a thread in the mailing list with a
> general approach to limiting backend memory consumption, but it is
> finished with no result.

It is a hard problem alright[1].

> The patch looks good as well as commentary.

Thanks, I will go ahead and push this now.

[1] https://www.postgresql.org/message-id/flat/CAAKRu_aLMRHX6_y%3DK5i5wBMTMQvoPMO8DT3eyCziTHjsY11cVA%40mail.gmail.com