On Tue, Jul 12, 2022 at 11:38 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
>
> On Tue, Jul 12, 2022 at 10:28 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> >
> >
> > I'm doing benchmark tests and will share the results.
> >
>
> I've done benchmark tests to measure the overhead introduced by doing
> bsearch() every time when decoding a commit record. I've simulated a
> very intensified situation where we decode 1M commit records while
> keeping builder->catchange.xip array but the overhead is negilible:
>
> HEAD: 584 ms
> Patched: 614 ms
>
> I've attached the benchmark script I used. With increasing
> LOG_SNAPSHOT_INTERVAL_MS to 90000, the last decoding by
> pg_logicla_slot_get_changes() decodes 1M commit records while keeping
> catalog modifying transactions.
>
Thanks for the test. We should also see how it performs when (a) we
don't change LOG_SNAPSHOT_INTERVAL_MS, and (b) we have more DDL xacts
so that the array to search is somewhat bigger
--
With Regards,
Amit Kapila.