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From: David Rowley <dgrowleyml@gmail.com>
Date: Tue, 1 Apr 2025 09:11:13 +1300
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Subject: Re: pgsql: Add memory/disk usage for Window aggregate nodes in
 EXPLAIN.
To: Christoph Berg <myon@debian.org>
Cc: Tatsuo Ishii <ishii@postgresql.org>, pgsql-hackers@lists.postgresql.org
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On Tue, 1 Apr 2025 at 04:40, Christoph Berg <myon@debian.org> wrote:
> -   Storage: Disk  Maximum Storage: NkB
> +   Storage: Memory  Maximum Storage: NkB
>     ->  Function Scan on generate_series a (actual time=N.N..N.N rows=N.N loops=N)

We'll probably just need to bump that 2000 row count to something a
bit more for 32-bit.

Any chance you could share the output of:

explain (analyze,buffers off,costs off) select sum(n) over() from
generate_series(1,2000) a(n);

Could you maybe also do a binary search for the number of rows where
it goes to disk by adjusting the 2000 up in some increments until the
Storage method is disk? (Not that I think we should set it to the
minimum, but it would be good to not set it too much higher than we
need to)

David