Re: pgsql: Add memory/disk usage for Window aggregate nodes in EXPLAIN. - Mailing list pgsql-hackers

From David Rowley
Subject Re: pgsql: Add memory/disk usage for Window aggregate nodes in EXPLAIN.
Date
Msg-id CAApHDvoZ4TeT2bSEaN+Nx94R0neBr1mmyDBx0Z5ZQXVUunu7JQ@mail.gmail.com
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In response to Re: pgsql: Add memory/disk usage for Window aggregate nodes in EXPLAIN.  (Christoph Berg <myon@debian.org>)
Responses Re: pgsql: Add memory/disk usage for Window aggregate nodes in EXPLAIN.
List pgsql-hackers
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



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