Re: Using per-transaction memory contexts for storing decoded tuples

Hi,

On Mon, Sep 16, 2024 at 10:56 PM Hayato Kuroda (Fujitsu)
<kuroda(dot)hayato(at)fujitsu(dot)com> wrote:
>
> Hi,
>
> > We have several reports that logical decoding uses memory much more
> > than logical_decoding_work_mem[1][2][3]. For instance in one of the
> > reports[1], even though users set logical_decoding_work_mem to
> > '256MB', a walsender process was killed by OOM because of using more
> > than 4GB memory.
>
> I appreciate your work on logical replication and am interested in the thread.
> I've heard this issue from others, and this has been the barrier to using logical
> replication. Please let me know if I can help with benchmarking, other
> measurements, etc.

Thank you for your interest in this patch. I've just shared some
benchmark results (with a patch) that could be different depending on
the environment[1]. I would be appreciated if you also do similar
tests and share the results.

Regards,

[1] https://www.postgresql.org/message-id/CAD21AoAaN4jaJ%3DW%2BWprHvc0cGCf80SkiFQhRc6R%2BX3-05HAFqw%40mail.gmail.com

--
Masahiko Sawada
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