Thread

Re: IPC/MultixactCreation on the Standby server

Andrey Borodin <x4mmm@yandex-team.ru> — 2025-12-02T13:44:21Z

> On 1 Dec 2025, at 20:29, Andrey Borodin <x4mmm@yandex-team.ru> wrote:
> 
> I'm looking through patchsets. I'll look in the morning with fresh eyes.

So far I have no findings.
I also tried to stress-test v14. I assumed that if regression slipped in, most probably it is inherited by 14 from higher versions.
I used slightly modified scripts from Dmitry who started this thread.

DB initialization:
create table tbl2 (id int primary key,val int);
insert into tbl2 select i, 0 from generate_series(1,100000) i;

Load with multi:
\set id random(1, 10000)
begin;
select * from tbl2 where id = :id for no key update;
savepoint s1;
update tbl2 set val = val+1 where id = :id;
commit;

Consistency test:
select sum(val) from tbl2;

Stress-test script:
while true; do pkill -9 postgres; ./pg_ctl -D testdb restart; (./pgbench --no-vacuum -M prepared -c 50 -j 4 -T 300 -P 1 postgres --file=load.sql &); sleep 5; done

To promote multixact races I tried this with patched version: added random sleep up to 50ms between GetNewMultiXactId() and RecordNewMultiXact().

So far I did not manage to corrupt database.

What else kind of loads worth exercising?


Best regards, Andrey Borodin.