Re: MultiXact\SLRU buffers configuration

Alexander Korotkov <aekorotkov@gmail.com>

From: Alexander Korotkov <aekorotkov@gmail.com>

To: Andrey Borodin <x4mmm@yandex-team.ru>

Cc: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>, Daniel Gustafsson <daniel@yesql.se>, Kyotaro Horiguchi <horikyota.ntt@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>

Date: 2020-10-27T17:02:20Z

Lists: pgsql-hackers

Attachments

v5-0001-Use-shared-lock-in-GetMultiXactIdMembers-for-offs.patch (application/octet-stream) patch v5-0001
v5-0002-Make-MultiXact-local-cache-size-configurable.patch (application/octet-stream) patch v5-0002
v5-0003-Add-conditional-variable-to-wait-for-next-MultXact.patch (application/octet-stream) patch v5-0003

On Mon, Oct 26, 2020 at 6:45 PM Andrey Borodin <x4mmm@yandex-team.ru> wrote:
> Thanks for your review, Alexander!
> +1 for avoiding double locking in SimpleLruReadPage_ReadOnly().
> Other changes seem correct to me too.
>
>
> I've tried to find optimal value for cache size and it seems to me that it affects multixact scalability much less than sizes of offsets\members buffers. I concur that patch 2 of the patchset does not seem documented enough.

Thank you.  I've made a few more minor adjustments to the patchset.
I'm going to push 0001 and 0003 if there are no objections.

------
Regards,
Alexander Korotkov

Commits

Rework new SLRU test with injection points
- 94a3373ac5c3 18.0 landed
injection_point: Add injection_points.stats
- 2e35c67f9568 18.0 landed
injection_points: Add initialization of shmem state when loading module
- b2b023aa3706 18.0 landed
Add injection-point test for new multixact CV usage
- 768a9fd5535f 18.0 landed
Use conditional variable to wait for next MultiXact offset
- a0e0fb1ba56f 17.0 landed
Improve performance of subsystems on top of SLRU
- 53c2a97a9266 17.0 landed
Adjust VACUUM hastup LP_REDIRECT comments.
- 325bc54eed4e 16.0 cited
Test replay of regression tests, attempt II.
- f47ed79cc8a0 15.0 cited