pá 19. 2. 2021 v 8:39 odesílatel Konstantin Knizhnik < k.knizh...@postgrespro.ru> napsal:
> > > On 19.02.2021 10:14, Pavel Stehule wrote: > > > > pá 19. 2. 2021 v 7:51 odesílatel Konstantin Knizhnik < > k.knizh...@postgrespro.ru> napsal: > >> >> >> On 18.02.2021 20:10, Pavel Stehule wrote: >> >> This has a negative impact on performance - and a lot of users use >> procedures without transaction control. So it doesn't look like a good >> solution. >> >> I am more concentrated on the Pg 14 release, where the work with SPI is >> redesigned, and I hope so this issue is fixed there. For older releases, I >> don't know. Is this issue related to Postgres or it is related to PgPro >> only? If it is related to community pg, then we should fix and we should >> accept not too good performance, because there is no better non invasive >> solution. If it is PgPro issue (because there are ATX support) you can fix >> it (or you can try backport the patch >> https://git.postgresql.org/gitweb/?p=postgresql.git;a=commitdiff;h=ee895a655ce4341546facd6f23e3e8f2931b96bf >> ). You have more possibilities on PgPro code base. >> >> >> Sorry, it is not PgPro specific problem and recent master suffers from >> this bug as well. >> In the original bug report there was simple scenario of reproducing the >> problem: >> >> CREATE TABLE toasted(id serial primary key, data text); >> INSERT INTO toasted(data) VALUES((SELECT string_agg(random()::text,':') >> FROM generate_series(1, 1000))); >> INSERT INTO toasted(data) VALUES((SELECT string_agg(random()::text,':') >> FROM generate_series(1, 1000))); >> DO $$ DECLARE v_r record; BEGIN FOR v_r in SELECT data FROM toasted LOOP >> INSERT INTO toasted(data) VALUES(v_r.data);COMMIT;END LOOP;END;$$; >> > > can you use new procedure_resowner? > > Sorry, I do not understanf your suggestion. > How procedure_resowner can help to solve this problem? > This is just an idea - I think the most correct with zero performance impact is keeping snapshot, and this can be stored in procedure_resowner. The fundamental question is if we want or allow more snapshots per query. The implementation is a secondary issue. Pavel > > -- > Konstantin Knizhnik > Postgres Professional: http://www.postgrespro.com > The Russian Postgres Company > >
